tame anatomy lectuering for mizan.t.pptx

MIZAN AMAN COLLEGE
OF
HEALTH SCIENCE
Introduction to human anatomy and physiology for Midwifery year one students
BY: kassahun k.

Learning objectives
At the end of this lesson the students will be
• To know anatomical terminologies which
describe position and body movement.
• To know anatomical terminologies of views and
plane.
• To describe and explain about a structure ,types
and function of cell.
• To understand body dev’t formation.
• To describe structure and function membrane.

Introduction
• The human body looks like a complicated
machine both in its structure and its function.
• It is the harmonious balance between this
structure and function that makes a human
being alive and functional.

1.1 General Anatomical Terminologies
Anatomy:- The word anatomy is derived from a Greek
word “Ana=upward, tome=to cut”.
It is the study of structure and the relationships
among structures.
Typically, when used by itself, the term 'anatomy'
tends to mean gross or macroscopic anatomy-that is,
the study of structures that can be seen without
using a microscopic. Microscopic anatomy, also called
'histology', is the study of cells and tissues using a
microscope.

Physiology:- is the study of how the systems of the
body work, and the way in which their integrated
cooperation maintains the health of the person.
 Shortly, physiology deals about the normal
functioning of the body.
When structure and function are coordinated the
body achieves a relative stability of its internal
environment called homeostasis/staying the
same.

Terminologies con’t......
Anterior/Ventral – toward thefront
Posterior/Dorsal –toward the back
Medial – towards the midline
Lateral – away from the midline
Proximal – near the point of origin
Distal – away from the point of origin
Superior / Cranial – towards the head
Inferior/ Caudal – down or toward the foot

Terminologies cont’..
Anterior/Ventral – toward thefront
Posterior/Dorsal –toward the back
Medial – towards the midline
Lateral – away from the midline
Proximal – near the point of origin
Distal – away from the point of origin
Superior / Cranial – towards the head
Inferior/ Caudal – down or toward the foot

Terminologies cont’…..
Eversion – turning the foot out
Inversion – turning the foot in
Pronation – turning the palm down
Supination - turning the palm up
Peripheral - Away from the central axis of the
body.

Anatomical Terminologies of Views & Planes
Body planes are imaginary surfaces or planes
or lines that divide the body into sections.
1. Sagital plane (lateral):- Divides the body into
right and left half.
a. Mid sagital plane: - divides body into equal
left and right halves.
b. Para sagital plane: - divides body into
unequal left and right.

Cont…
2. Frontal plane (coronal): - divides the body
into asymmetrical anterior and posterior
sections.
3. Transverse plane (axial): - divides the body
into upper and lower body section.
4. Oblique plane: - divides the body obliquely
into upper and lower section.

tame anatomy lectuering for mizan.t.pptx

1.2 Cell structures and types
Cell is the basic living structural and functional unit of
the body. All life depends on the many chemical
activities of cells.
It is the smallest unit of life that is classified as a living
thing, and is often called the building block of life.

Principles of Cell Theory
• All living things are made of cells.
• Smallest living unit of structure and
function of all organisms is the cell.
• All cells arise from preexisting cells
(this principle discarded the idea of
spontaneous generation).

There are four main parts of cell:
1. Plasma (cell) membrane: separating the cell internal
parts from external environment.
2. Cytoplasm: is the substance that surrounds organelles.
3. Organelles: are permanent structures which found in the
cytoplasm.
4. Inclusions: they are the secretions and storage products
of cells.

Plasma Membrane
• It is a thin double layered membrane made of phospholipids,
cholesterol, glyco-lipid, & carbohydrate (oligosaccharides).
Functions of cell membrane:
1. Separate cell from one another.
2. Provide an abundant surface on which chemical reaction can occur.
3. Regulate the passage of materials into and out of cells (selective
permeability).

Functions cont’…
4. Separate the cytoplasm from extra cellular
fluid.

Transport across cell membrane
 Movements across membrane take place in two ways.
1. Passive transport- not requires energy. Like diffusion, facilitated
diffusion, osmosis and filtration.
2. Active transport- it requires energy (as ATP) to transport across
the membrane from the area of low concenteration to area of high
water concenteration. Like endocytosis and exocytosis.

Types of passive transport
A. Simple diffusion: movements of molecules from area of
high concentration to the area of low concentration.
B. Facilitated diffusion: it is a type of diffusion which
needs carrier proteins to carry on like glucose.
 No direct energy is needed here.

C. Osmosis: a special type of diffusion referring to the passage of
water through a selectively permeable membrane from an area of high
water concentration to lower water concentration.
solvent + solute = solution
• Hypotonic
– Solutes in cell more than outside
– Outside solvent will flow into cell
• Isotonic
– Solutes equal inside & out of cell
• Hypertonic
– Solutes greater outside cell
– Fluid will flow out of cell
D. Filtration: small molecules pass through selectively permeable membrane
in response to force of pressure. Example: - filtration in the kidney in the
process of urine formation.

Transport in vesicles
Endocytosis- Materials moves into a cell in a vesicle
formed from the plasma membrane. Three forms of
endocytosis are pinocytosis, phagocytosis, and receptor-mediated
endocytosis.
i. Pinocytosis is a form of endocytosis in which cells
engulf liquids.
ii. Phagocytosis is a form of endocytosis in which the
cell takes in larger particles, such as a white blood cell
engulfing a bacterium.
iii. Receptor-mediated endocytosis -allows the cell to take
in very specific molecules (ligands) that pair up with specific
receptors on the cell surface.

Exocytosis, opposite to Endocytosis, used to remove out
undigested particles. It is especially important in two
types of cells:
1. Secretory cells that liberate digestive enzymes,
hormones, mucus, or other secretions.
2. Nerve cells that release substance called
neurotransmitters.

Cytoplasm
It is a matrix or ground substance in which various cellular
components are found.
Organelles:Organelles are specialized portion of the cell with a
characteristic shape that assume specific role in growth, maintenance,
repair and control.

Organelles cont’..
1. Nucleus
 Oval in shape and is the largest structure in the cell.
 Contain the hereditary factor in the cell.
 It controls cell activity & structure.

2. Ribosome, tiny granules, composed of Ribosomal RNA (rRNA).
They are site of protein synthesis.
3. Endoplasmic reticulum
 Various products are transported from one portion of the cell to
another via the endoplasmic reticulum.
 It is also storage for synthesized molecules. Together with the
Golgi complex it serves as synthesis & packaging center.

Two types of endoplasmic reticulum
a. Granular ER(Rough)- Containing granule and
involving in synthesis of protein.
• Ribosomes attached to surface
– Manufacture proteins
– Not all ribosomes attached to rough ER
• May modify proteins from ribosomes
b. A Granular ER(smooth) - that synthesize lipid &
involves in detoxification.
• No attached ribosomes
• Has enzymes that help build molecules
– Carbohydrates
– Lipids

4.Golgi complex - It process, sort, pack & deliver protein to various
parts of the cell.
5. Mitochondria - a small, spherical, rod shaped or filamentous
structure. It generate energy and why it is said power house of
cell.
6. Lysosomes – It formed from Golgi complexes & have single
membrane. They contain powerful digestive (hydrolytic enzyme).

Functions of the cells
Some of the basic functions of cell are:
growth,
metabolism,
irritability and
reproduction

Cell Types
• Prokaryotic
• Eukaryotic

Prokaryotic Cells
• First cell type on earth
• Cell type of Bacteria and Archaea.

Prokaryote Characteristics
1. Simplest organisms: Very small size.
2. Lack membrane-bound organelles inside the cell.
3. have few internal structures that are distinguishable under a
microscope.
4. genetic information is in a circular loop called a plasmid
(instead of having chromosomal DNA).
5. Strong cell walls: resistant to environmental changes.

Prokaryote Functions
• decomposers
• agents of fermentation
• play important roles in digestive systems
• involved in many nutrient cycles
– ex: the nitrogen cycle, which restores nitrate into the soil for plants.
• diverse array of metabolic functions.
– For example, some bacteria use sulfur instead of oxygen in their
metabolism.

Eukaryotic Cells
• Nucleus bound by membrane.
• Include fungi, protists, plant, and animal cells.
• Possess many organelles.

Prokaryote & Eukaryote similarities
Both have
1. DNA
2. A cell membrane
3. Ribosomes
4. Diverse forms (meaning a lot of shapes and
sizes)

Prokaryotes & Eukaryotes differences
Prokaryotes Eukaryotes
•Plasmid DNA
•No membrane-
bound organelles
•Few things inside
(are simple)
•Nuclear bound DNA
•Has membrane
bound organelles
•Many things inside
(Are complex)
**Organelles are tiny structures inside cells that do a
certain job.

Characteristic Prokaryote Eukaryote
Size 1-10um 10-100um
Nuclear Envelope Absent present
Chromosomes Single, circular, no
nucleus
Multiple, linear, wound on
nucleosomes
Golgi apparatus Absent Present
ER, Lysosomes Absent Present
Mitochondria Absent Present
Chlorophyll Not in chloroplasts Present in chloroplasts
Ribosomes Relatively small Relatively large
Microtubules,
filaments,
microfilaments
Absent Present
Flagella Lack microtubules Contain microtubules

1.3 Tissue structure and types
A tissue is resembled of cells, not necessarily
identical, but from the same origin.
The various tissues of the body are divided in
to four groups. These are epithelial,
connective, nervous and muscle tissue.

Tissue cont’’…
1. Epithelial tissue: - Found in the outer layer of skin,
lining of organs (viscera), blood and lymph vessels
and body cavities.
 Epithelial cells also form the endocrine glands
(pituitary, parathyroid, thyroid, adrenals, ovary, and
testis), and the exocrine glands (e.g, salivary glands,
pancreas and liver).

Tissue cont’..
2.Connective tissue:It Connects and supports
most part of the body. They constitute most
part of skin, bone and tendons.

Tissue cont’…
3. Muscle tissue: - It consists of highly
specialized cells, which provide motion,
maintenance of shape & body heat
production.

Tissue cont’…
4. NERVOUS TISSUE: - Found in the brain, spinal
cord and nerves.
 it contains two principal cell types: neurons &
neuroglia.
 Neurons are nerve cells those are sensitive to
various stimuli.

1.4 Organ and System
 Organ is an integrated collection of two or
more kinds of tissue that works together to
perform specific function.
For example: Skin is an organ formed from
epithelial, connective, muscle and nerve
tissue.

Cont..
System is a group of organs that work together
to perform major function. For example:
Respiratory system contains several organs.
Organism level:-The various organs of the
body form the entire organism.

MEMBRANES
There are three kinds of membranes
1. Mucous Membrane (Mucosa):- lines body
cavities that open directly to the exterior & it is
epithelial layer.
 It lines the entire gastrointestinal, respiratory,
excretory & reproductive tracts.

Membranes cont’..
2. Serous Membrane (Serosa):- contains loose
connective tissue covered by a layer of
mesothelium.
It lines body cavities that do not open directly to
the exterior & it covers the organs that lie within
the cavity.

Membranes cont’..
3. Synovial Membrane: - it doesn’t contain
epithelium unlike other membranes do.
It lines the cavities of the freely movable
joints.
• It secretes a synovial fluid

Learning objectives
Chapter two
• To describe structure and function of skin and
skin appendages.

The Integumentary System
• Integument is skin.
• Skin and its appendages make up the
integumentary system.
• A fatty layer (hypodermis) lies deep to it.
• Two distinct regions.
– Epidermis.
– Dermis.

The skin
The skin is the largest organ of the body,
with a total area of about 22 square feet
and weights about 7% of total body
weight.

Structures of the skin
1. Epidermis: is the outermost layer, it contains melanin,
which determines the color of our skin.
It has no nerve supply or blood vessels.
• Keratinized stratified squamous epithelium.
• Four types of cells
– Keratinocytes – deepest, produce keratin (tough fibrous protein).
– Melanocytes - make dark skin pigment melanin .
– Merkel cells – associated with sensory nerve endings .
– Langerhans cells – macrophage-like dendritic cells.

Layers (from deep to superficial)
– Stratum basale or germinativum – single row of cells attached to
dermis; youngest cells.
– Stratum spinosum – spinyness is artifactual; tonofilaments (bundles of
protein) resist tension.
– Stratum granulosum – layers of flattened keratinocytes producing
keratin (hair and nails made of it also).
– Stratum lucidum (only on palms and soles).
– Stratum corneum – horny layer (cells dead, many layers thick).

Epithelium: layers (on left) and cell types (on right)

Dermis
• Strong, flexible connective tissue: your “hide”.
• Cells: fibroblasts, macrophages, mast cells, WBCs.
• Fiber types: collagen, elastic, reticular.
• Rich supply of nerves and vessels.
• Critical role in temperature regulation (the vessels).
• Two layers (see next slides).
– Papillary – areolar connective tissue; includes dermal
papillae.
– Reticular – “reticulum” (network) of collagen and reticular
fibers.

*Dermis layers
*
*
*Dermal papillae

Hypodermis
• “Hypodermis” (Gk) = below the skin.
• “Subcutaneous” (Latin) = below the skin.
• Also called “superficial fascia”.
“fascia” (Latin) =band; in anatomy: sheet of connective tissue.
• Fatty tissue which stores fat and anchors skin
(areolar tissue and adipose cells).
• Different patterns of accumulation
(male/female).

Skin color
• Three skin pigments.
– Melanin: the most important.
– Carotene: from carrots and yellow vegies.
– Hemoglobin: the pink of light skin.
• Melanin in granules passes from melanocytes
(same number in all races) to keratinocytes in
stratum basale.
– Digested by lysosomes.
– Variations in color.
– Protection from UV light vs vitamin D?

Functions of the skin
Heat regulation.
Protection.
Fluid regulation.
Sensory reception.
Synthesis of vitamin.

Skin appendages
• Derived from epidermis but extend into
dermis.
• Include
– Hair and hair follicles.
– Sebaceous (oil) glands.
– Sweat (sudoiferous) glands.
– Nails.

Hair and hair follicles: complex
Derived from epidermis and dermis
Everywhere but palms, soles, nipples, parts of genitalia
*“arrector pili” is smooth muscle
*
Hair papilla
is connective
tissue________________
Hair bulb:
epithelial cells
surrounding
papilla

• Functions of hair
– Warmth – less in man than other mammals
– Sense light touch of the skin
– Protection - scalp
• Parts
– Root imbedded in skin
– Shaft projecting above skin surface
• Make up of hair – hard keratin
• Three concentric layers
– Medulla (core)
– Cortex (surrounds medulla)
– Cuticle (single layers, overlapping)

• Types of hair
– Vellus: fine, short hairs.
– Intermediate hairs .
– Terminal: longer, courser hair
• Hair growth: averages 2 mm/week
– Active: growing.
– Resting phase then shed.
• Hair loss
– Thinning – age related.
– Male pattern baldness.
• Hair color
– Amount of melanin for black or brown; distinct form of
melanin for red.
– White: decreased melanin and air bubbles in the medulla.
– Genetically determined though influenced by hormones and
environment.

Sebaceous (oil) glands
• Entire body except palms and soles.
• Produce sebum by holocrine secretion.
• Oils and lubricates.

Sweat glands
• Entire skin surface
except nipples and
part of external
genitalia.
• Prevent overheating
• 500 cc to 12 l/day! (is
mostly water).
• Humans most
efficient (only
mammals have).
• Produced in response
to stress as well as
heat.

Types of sweat glands
• Eccrine or merocrine
– Most numerous.
– True sweat: 99% water, some salts, traces of waste.
– Open through pores.
• Apocrine
– Axillary, anal and genital areas only.
– Ducts open into hair follices.
– The organic molecules in it decompose with time – odor.
• Modified apocrine glands
– Ceruminous – secrete earwax.
– Mammary – secrete milk.

Nails
• Of hard keratin.
• Corresponds to hooves and claws.
• Grows from nail matrix.

Chapter-3
Introduction to skeletal system
Learning objective:
At the end of this unit you will be able to:
• Discuss the functions of bones and
the skeletal system.
• Classify bones on the basis of their
shape and location.
• Describe the anatomical feature of fetal skull

Cont’…
The skeletal system consists of the entire
framework of bones and their cartilages, along
with the ligaments and tendons.
Bone tissue is a type of highly specialized dense
connective tissue and it continuously growing,
remodeling and repairing itself.

Introduction to bone
Bone tissue makes up to 18% of the
weight of human body.
Bone is more rigid than other tissues
because it contains inorganic salts mainly
calcium phosphate & calcium carbonate.

Types of bone by size and shape
1. Long bone are called long as its length is greater than its
width.eg femur,humerus..
2. Short bones are somewhat cube shaped and are nearly
equal in length and width.eg Bones in wrist,ankle.
3. Flat bones are thin or curved more often they are flat. This
includes ribs, scapulae, sternum and bone of cranium.

Cont’...
4. Irregular bones have complex shapes and they do not fit
neatly into any other category. Examples are the vertebral,
facial, hip bone and the calcaneus bone.
5. Sesamoid bones are small bones embedded within certain
tendons, the fibrous cord that connects muscle to bones.
 Typical sesamoid bones are patella and pisiform carpal bone.

Types of bones by cell arrangement
Bone is not completely solid but has many
small spaces between its cells and extracellular
matrix components.
Some spaces serves as channels for blood
vessels that supply bone cells with nutrients.

Cont…
Depending on the size and distribution of the
space, bone may be categorized as compacted
and spongy.
Overall, about 80% of skeleton is compact
bone and 20% is spongy bone.

Cont..
1.Compact /cortical bone tissue;-it contains of
few spaces and is the strongest form of bone
tissue. Outer layer of bone, very hard and
dense.
Compact bone tissue provides protection,
support and resists the stresses produced by
weight and movements.

Cont…
2. Spongy /cancellous bone tissue; - it also
referred to as trabecular or cancellous bone
tissue, does not contain osteons.
It is always located in the interior of the bone,
protected by a covering of compact bone.

Bone cells.
There are four types of cells in the bone tissue:
1. Osteogenic cells; -bone producing cells.
 They are the only bone cells to undergo cell
division; the resulting cells develop into osteoblasts.
2. Osteoblast cells; - are bone building cells and they
initiate calcification.

cont.…
3. Osteocytes; - are mature bone cells, are the main
cells in the bone tissue and maintain its daily
metabolism.
4. Osteoclast;- are bone breaking cells and releases
powerful lysosomal enzymes and acid that digest
protein and mineral components of the underlying
extracellular bone matrix.

Bone formation and development
 The process by which bone forms is called ossification or
osteogenesis.
 Bone formation follows one of two patterns
1. Intramembranous ossification;-bone forms directly within
mesenchyme.
2. Endochondral ossification;-it is the process by which bone is
formed from the cartilage tissue.

Gross Anatomy of a Long Bone
· Diaphysis
·Shaft
·Composed of
compact bone
· Epiphysis
·Ends of the bone
·Composed mostly of
spongy bone

Structures of a Long Bone
· Periosteum
· Outside covering of
the diaphysis
· Fibrous connective
tissue membrane
· Sharpey’s fibers
· Secure periosteum to
underlying bone
· Arteries
· Supply bone cells
with nutrients

Con’t
· Articular cartilage
·Covers the
external surface of
the epiphyses
·Made of hyaline
cartilage
·Decreases friction
at joint surfaces

Con’t
Medullary cavity
·Cavity of the shaft.
·Contains yellow marrow (mostly fat) in
adults.
·Contains red marrow (for blood cell
formation) in infants.
Metaphysis - is the part separating diaphysis
from epiphysis

Functions of the skeletal system
1. Support: - serves as the structural framework for
the body by supporting soft tissues.
2. Protection: - it protects the most important
internal organs from injury.
3. movement:- Muscles, bones, and joints provide
the principal mechanics for movement.

Cont…
4.Mineral homeostasis (storage and release); -
bone tissue store 99% of the body calcium. On
demand it releases minerals into the blood.
5. Blood cell production;- red bone marrow
produce RBCs,WBCs, and platelets, a process
is called hematopoiesis.

Skeletal classifications
The Adult human skeletons have 206 named
bones that are grouped in to two principal
parts.
The axial (80 bones) and appendicular (126
bones) skeleton.

The Axial Skeleton
• Axial division
– Skull and associated
bones:
• Auditory ossicles
• Hyoid bones
– Vertebral column
– Thoracic cage
• Ribs + sternum

Axial skeleton.
• It is composed of bones that lie on the
imaginary longitudinal axis of the body.
• It includes the skull,spine,ribs and sternum.

Appendicular skeleton
• They constitute bones outside the
longitudinal axis of the body and are specially
bones in the upper and lower extremities.

Classification of Axial skeleton
• The bones in axial skeleton are generally
divided into three parts:
• bones of the skull
• bones of the vertebral column
• bones of thorax

1.The skull
1. Skull bones; - Consist of cranial and facial bones.
 Posses sinuses (frontal, maxillary, ethmoidal and
sphenoidal).
- Helps to reduce weight of skull and give
resonance to voice.

CONT..
 Have foramina to permit passage of blood vessels,
nerves and other structures.
 Foramen magnum is the largest of all which allows
part of brain, spinal cord and vertebral vessels.

The skull cont’..
A. Cranial bones (Calvaria/Brain case)
Protects brain.
Composed of 8 flat bones these are:
Frontal bone (01)
Parietal bones(02)

The skull cont’..
Occipital bone (1)
Temporal bones (2)
Sphenoid bone (1)
Ethmoid bone (1)

Features of cranial bones
Sutures
Sutures are immovable joints found between
skull bones except the mandible contact with
the cranium and they are fibrous joints where
cranial bones meet.

There are four main sutures in the skull
1. Coronal suture :- B/n the frontal and the two parietal
bones.
2. Sagital suture :- B/n the two parietal bones.
3. Lambdoidal suture :- B/n two parietal bones and
occipital bone
4. Squamosal suture :- B/n parietal bones and temporal
bones

Anatomy of fetal skull
Fontanels
• At birth, the cranial bones are connected by
areas of fibrous connective tissue.
• At birth, the membrane filled spaces on the
skull are called Fontanels, are areas where
sutures meet.

Cont..
Function of fontanels
It enable the skull of the fetus to compress as it passes
through the birth canal (permit molding during birth).
Permit the rapid growth of a brain during infancy.
Serves as a land mark (anterior fontanel) for withdrawal
of blood from the superior sagital sinus.
Aid in determination of fetal position prior to birth.

Cont’..
There are Six prominent fontanels in the skull:
1. Anterior (frontal) fontanel
Is b/n the angle of two parietal bones and the segment of the frontal
bone.
It is diamond shaped and is the largest fontanel.
It closes 18 to 24 months after birth.

Cont…
3. Antero-lateral (sphenoidal) fontanels
Are a pair, one on each side.
They are found at the junction of frontal,
parietal, temporal and sphenoidal bones.
Small and irregular in shape.
Close of the third (3rd
) month after birth

Cont…
2. Posterior (occipital) fontanel
Is b/n parietal and occipital bones.
Smaller than the anterior fontanel.
It closes 2 months after birth.

Cont…
4.Postero-lateral (mastoid) fontanels
Are paired, one on each side.
Found at the junction of parietal, occipital and temporal
bones.
Irregular in shape.
Begin to close at 1 or 2 months after birth and
completely by 12 months.

Fontanelles
The Skull of an Infant.

Fontanelles
15b The Skull of an Infant.

B. Facial bones
Consists of about 14 bones.
Provide the basic shape of the face.
All are paired except vomer and mandible.

Facial bones cont’..
These 14 bones are:
• Lacrimal (2)
Inferior nasal conchii (2): - lateral walls of nasal
cavities, shaped like curved leaves.
Nasal (2): - upper bridge of nose, attached to nasal
cartilage

Cont…
Vomer (1): - forms posterior & inferior nasal
septum dividing nasal cavities.
Mandible /lower jaw (1): - is the largest &
strongest facial bone.
Maxillae/upper jaw (2): - Forms upper jaw,
front of hard palate & part of eye sockets.

Cont…
Palatine (2): - posterior part of hard palate,
floor of nasal cavity & orbit; posterior to
maxillae.
Zygomatic/molar (2): - cheekbones, below and
lateral to orbits of the eye.

14 Facial Bones
Nasal (2) Maxillae (2) Zygomatic (2)
Mandible (1) Lacrimal (2) Palatine (2)
Inferior nasal conchae (2) Vomer (1)

Ossicles of ear (Auditory Ossicles)
Three auditory ossicles in the middle ear of
each ear; Malleus (hammer), Incus (anvil) &
Stapes (stirrup).
Helps to transmit sound impulses from ear
drum to oval window.

Hyoid bone
Located below root of tongue, above
(superior) to larynx.
U- Shaped & is site of attachment for muscles
used in speaking and swallowing.
Does not articulate with any other bone.

Vertebral column
It is also called spinal column and it extends from
skull to pelvis.
 It Composed of 26 vertebral bones, but during early
development they were 33 bones.
The cervical, thoracic & lumbar vertebras are
movable, but the sacral & coccygeal are immovable.

Cont..
Functions of Vertebral column
 Supports head, trunk and upper extremities.
 Allowing movement by rotating and moving forward,
backward & sideways.
 Protects spinal cord and nerves.
 Provide attachment for muscles, ribs and vertebral
structures.

Cont..
Abnormal curvatures of the vertebral column:
Scoliosis ( abnormal lateral curvatures).
Kyphosis (abnormal posterior curvature –
hunch back).
Lordosis (abnormal anterior curvature – sway
back).

The Vertebral Column
Abnormal Curvatures of the Spine.

Cont..
Inter-vertebral Discs
Between adjacent vertebrae from 2nd
cervical
to sacrum there are intervertebral discs which
are composed of fibro-cartilage.

Cont..
Cervical vertebrae (7) ;- The 1st
cervical vertebrae is called
Atlas
and it supports head, permits “Yes” motion of head at joint b/n
skull and Atlas. Has no body or spinous process.
The 2nd
Cervical vertebra is called Axis and it
Permits “No” Motion in at joint b/n Axis and
Atlas. Has heavy spinous process.

Vertebral Regions
The Cervical Vertebrae.

Cont’..
Thoracic vertebrae (12):
Are relatively larger & stronger than cervical
vertebras & articulate with ribs. Allows rotation
and prevents flexion and extension.
Lumbar vertebrae (5):
– Largest and strongest vertebrae. Allows flexion and
extension – rotation prevented. Triangular vertebral foramen
– Superior articular processes
• Face up and in
– Inferior articular processes
• Face down and out

Vertebral Regions
The Lumbar Vertebrae.

Vertebral Regions
The Thoracic Vertebrae.

Cont’..
Sacrum (1)
 It has 5(five) fused bones and decreases in size down.
 Support vertebral column & serves as a strong
foundation for pelvic girdle.
• Forms the posterior wall of pelvis.
• Superior surface articulates with L5.
• Inferiorly articulates with coccyx

Cont’..
Coccyx (1):
It is a small triangular tail bone formed by
fusion of 4 coccygeal vertebrae which usually
occurs b/n age of 20-30 years.

Thorax
It is the superior part of the trunk, b/n the neck &
abdomen.
The thorax are formed by the sternum (breast
bone), costal cartilage, ribs and bodies of the
thoracic vertebra.
The thoracic cage encloses & protects the organs
in the thoracic cavity.

Cont’..
Sternum (breast bone):- It is a flat bone, has 3 fused bones:
Manubrium, body and xiphoid process.
Manubrium
– The superior portion of sternum.
– Broad, triangular shape.
– Articulates with clavicles (collarbones) .
– Articulates with cartilages of first rib pair.
– Has a jugular notch, a shallow indentation between clavicular
articulations.

• The sternal body
– Is tongue-shaped
– Attaches to the manubrium
– Attaches to costal cartilages of ribs 2–7
• The xiphoid process
– Is the smallest part of the sternum
– Attaches to the sternal body
– Attaches to diaphragm and rectus abdominis muscles

Cont..
Ribs
12 pairs and it is connect directly to
corresponding thoracic vertebrae in the back.
The space b/n ribs, called intercostal spaces,
are occupied by intercostals muscles, blood
vessels and nerves.

Cont..
Types of Ribs by attachment with sternum
1. True ribs (vertebro-sternal ribs): The 1st
-7th
ribs
2. False ribs (vertebro-chondral ribs): 8th
-10th
ribs
and their cartilages attach one on other and then
attach to the cartilage of the 7th
rib.
3. Floating ribs: The 11th
and 12th
and their anterior
part doesn’t attach even indirectly to the sternum.

Bones of the Appendicular skeleton
The functionally of Appendicular
skeleton is locomotion (Lower limbs) of
the axial skeleton and manipulation of
objects in the environment (Upper limbs).

Cont..
Divisions of Appendicular skeleton:
1. Pectoral Girdles (4 bones) - Left and right
Clavicle(2) and Scapula(2).
2. Arm and Forearm (6 bones) - Left and right
Humerus(2), Ulna(2) and Radius(2).

Cont..
3. Hands (58 bones) - Left and right Carpal (16),
Metacarpal (10), phalanges (28).
4. Pelvis (2 bones) - Left and right.

Cont..
5. leg (8 bones)- Femur (2), Tibia (2), Patella (2),
and Fibula (2).
6. Feet (56 bones)-Tarsals (14), Metatarsals (10),
phalanges (28).

Pectoral girdle (shoulder girdle)
These bones are attached only anteriorly to the
axial skeleton on sternum.
They Connects the appendicular skeleton to the
axial bones. Connects with the axial skeleton only
at the manubrium(claviculosternal joint)
Functions in muscle attachment and movement of
arm and fore arm.

The Clavicles
• Also called collarbones
• Long, S-shaped bones
• Originate at the manubrium (sternal end)
• Articulate with the scapulae (acromial end)

The Scapulae
• Also called shoulder blades
• Broad, flat and triangular
• Articulate with arms and collarbone

Bones of the Upper Limb (UL)
1. ARM bone/ Humerus; - arm is the part b/n the
shoulder and elbow.
Humerus is the largest and longest bone in the
Upper limb.
Articulates with scapula at Scapula - Humeral
joint at shoulder and with radius and ulna at
elbow.

BONES OF FORE ARM
1. Radius - is the smaller bone of the forearm
and is located on the lateral aspect of the
forearm.
2. Ulna- Medial and longer one of the forearm
bones and its Olecranon process located on the
proximal end & fits with olecranon fossa of
Humerus.

Bones of the hand
1. Carpal bones, joined to one another by ligaments
and the articulations among carpal bones are
called intercarpal joints.
Short bones.
Composed of 8 (eight) carpal bones (in each
wrist).
Arranged in two transverse rows of 4 bones.

Cont..
Mnemonic for carpal bone: - Stop Letting
Those People Touch The Cadavers Hand.
Scaphoid  Lunate  Triquetrum 
Pisiform.
Trapezium  Trapezoid  Capitate Hamate

Metacarpal Bones
• The 5 long bones of the hand
• Numbered I–V from lateral
(thumb) to medial
• Articulate with proximal
phalanges

Phalanges of the Hands
• Thumb:
–2 phalanges (proximal, distal)
• Fingers:
–3 phalanges (proximal, middle,
distal)

The Pelvis
• Consists of 2 ossa coxae, the
sacrum, and the coccyx
• Stabilized by ligaments of
pelvic girdle, sacrum, and
lumbar vertebrae

The OSSA COXAE
• Also called hipbones.
• Strong to bear body weight &stress of
movement.
• Each is made up of 3 fused bones:
–ilium (articulates with sacrum).
–Ischium.
–Pubis.

The Acetabulum (vinegar cup)
• Also called the hip socket.
• Is the meeting point of the ilium,
ischium, and pubis .
• Articulates with head of the
femur (Hip joint)).

Bones of the lower limb (LL)
Lower limbs are connected to the Axial
skeleton by pelvic girdle.
General function of LL
It Supports body weight, Locomotion and
Maintain equilibrium.

Cont..
Four parts of Lower limb
Hip from iliac crest to thigh.
Thigh  b/n hip and knee.
Leg b/n knee and Ankle.
Foot distal to ankle.

CONT..
Skeleton of the thigh, leg and feet: Femur, Patella,
Tibia and fibula, Tarsus, Metatarsus and Phalanges.
Femur
Is typical long bone which is the longest, strongest
& heaviest bone in our body.
Supports body and transmits weight to lower leg.

The Femur (longest, heaviest )

CONT..
Tibia & Fibula: long bone of leg
 Tibia is larger long bone of legs which
located medially and transmit weight to the
foot.
 Fibula is smaller doesn’t transmit weight, but
provide stability & strength for ankle joint.

CONT..
Ankle/Foot bones
Tarsus (7 in each feet), are part of short bone and
consists Talus, Calcaneous, Navicular, 03
Cuneiforms and Cuboid.

The Ankle
• Also called the tarsus:
– consists of 7 tarsal bones

Feet: Metatarsal Bones
• 5 long bones of foot .
• Numbered I–V, medial to lateral.
• Articulate with toes.

Toes: Phalanges
• Phalanges:
– bones of the toes
• Hallux:
– big toe, 2 phalanges (distal, proximal)
• Other 4 toes:
– 3 phalanges (distal, medial, proximal)

CONT..
Mnemonic for Tarsal’s bone
Tall Centers Never Take Short From Corner.
Talus, Calcaneus, Naviculars, Thrid cuneiform
Second cuneiform, First cuneiform, Cuboid.

Articulations (joints)
Articulations (joints) are places where two
adjacent bones or cartilages meet.

Classification of articulations
Joints are classified by two methods
By function-degree of movement.
By structure – presence of cavity.

Functional classification
immovable (synartherosis),
slightly movable (amphiartherosis) and
 freely movable (diarthrosis).

Structural classification
1. Fibrous joints – fibrous connective tissue
unites articulating bones which has no joint
cavity. Immovable joints.
E.g. Cranial sutures in children.

CONT..
2. Cartilaginous joints
Articulating bones united by plate of hyaline
cartilage. E.g. symphysis pubis.
3. Synovial joints
Articulating bones moving freely along smooth,
lubricated articular cartilage. They are movable
joints.

Types of synovial joint
A. Hinge joint- convex surface of one bone is fitted into
concave surface of other bone – flexion, extension E.g.
elbow.
B. Pivot joint- supination, pronation, rotation. E.g.
proximal radio-ulnar joint.
C. Ball and socket- flexion, extension, adduction,
abduction. E.g shoulder joint, hip joint.

Chapter.4 The muscular system
Learning objectives:
At the end of this chapter you will be able
• To know structure and function of skeletal,smooth and cardiac
muscles.
• To describe connective tissue and nerve supply to muscles.
• To know physiology of stimulation and contraction of muscle.
• To know categories muscle groups.
• To differentiate different weak places in the abdomen.
Prepared by kassahun k(BSC)

Cont’…
Introduction
Muscular tissue contributes to the homeostasis
by producing body movements, moving
substances through the body, and producing
heat to maintain normal body temperature.

Cont’…
Muscular tissues consist of elongated cells
called muscle fibers or myocytes that can use
ATP to generate force.

Types of muscle tissue
1. Skeletal muscle tissue
Is a muscle tissue mostly attached to bones and
moves bone of the skeletons and has a limited
capacity for regeneration.
Skeletal muscles also are controlled subconsciously
to same extent; for example, diaphragm.

• Cells are multinucleate
• Striated – have visible banding
• Voluntary – subject to conscious control
• Cells are surrounded and bundled by
connective tissue

2 Cardiac Muscle Characteristics
• Has striations
• involuntary
• Usually has a single
nucleus
• Joined to another muscle cell
at an intercalated disc
• Found only in the heart.
• Cardiac muscle can’t
regenerate.

3 Smooth Muscle Characteristics
• Has no striations
• Spindle-shaped cells
• Single nucleus
• Involuntary – no conscious
control
• Found in walls of hollow
organ, blood vessels, eye,
glands, uterus, skin
• Better regeneration capacity
than skeletal and cardiac
muscles.

Comparisons Among Skeletal, Smooth, and Cardiac Muscle

Functions of muscle tissue
1. Producing body movements
2. Stabilizing body positions
3. Storing and Moving substances within
the body
4. Generating heat (Thermo-genesis)

Properties of muscular tissue
1. Excitability (irritability):- ability to
respond to certain stimuli by producing
electrical signals.
2. Contractibility: - ability to contract
(shorten and thicken) when stimulated by
action potentials.

Cont…
3. Extensibility: - ability to stretch (extend)
without being damaged.
4. Elasticity:-ability to return to its original
shape after contraction or extension.

Structures of skeletal muscles
Each skeletal muscle is a separate organ
composed of hundreds to thousands of
skeletal muscle cells called muscle fibers.
Skeletal muscle also contains connective
tissues surrounding muscle fibers.

Three layers of connective tissue
1. Epimysium: - outermost layer of connective
tissue that wraps the entire muscle.
2. Perimysium: - a connective tissue that
surrounds groups of 10 to 100 or more muscle
fibers and holds bundles of muscle fibers
called fascicles.

CONT…
3. Endomysium: - a connective tissue that wraps
each individual muscle fiber.
Epimysium, perimysium and endomysium
extend beyond the muscle as a tendon, which
is a cord of connective tissue that attaches a
muscle to a bone.

Connective Tissue Wrappings of Skeletal
Muscle

Skeletal Muscle Attachments
• Epimysium blends into a connective tissue
attachment
– Tendon – cord-like structure
– Aponeuroses – sheet-like structure
• Sites of attachment
– Bones
– Cartilages
– Connective tissue coverings

• Muscle attachments
– Most skeletal muscles
run from one bone to
another
– One bone will move –
other bone remains fixed
• Origin – less movable
attachment
• Insertion – more
movable attach-
ment

• Muscle attachments (continued)
– Muscles attach to origins and insertions by
connective tissue
• Fleshy attachments – connective tissue fibers are short
• Indirect attachments – connective tissue forms a tendon or
aponeurosis
– Bone markings present where tendons meet bones
• Tubercles, trochanters, and crests

Nerve and blood supply
Skeletal muscles are well supplied with nerves and
blood vessels.
The neurons that stimulate the muscle to contract are
somatic motor neurons.
Skeletal muscle tissues contract only when stimulated
by acetylcholine released by nerve impulses.

Microscopic anatomy of muscle
• Each muscle fiber is contains several nuclei, covered by a plasma membrane
called sarcolemma.
Sarcolemma - cell membrane
– Surrounds the sarcoplasm (cytoplasm of fiber)
• Contains many of the same organelles seen in other cells
• An abundance of the oxygen-binding protein myoglobin
– Punctuated by openings called the transverse tubules (T-tubules)
• Narrow tubes that extend into the sarcoplasm at right angles to the surface.
• Filled with extracellular fluid
 The cytoplasm of the fibers called a sarcoplasm is filled with myofibrils.
 Myofibril is a thread – like structure that extends from one end of the muscle fiber
to the other. It is cylindrical structure with in muscle fiber.

Cont…
Myofibril consists of two types of protein filaments:
Actins (thin myofilaments) & Myosin (thick
myofilaments).
The two myofilaments form highly ordered units called
sarcomers, which are joined end-to-end to form the
myofibrils.
Sarcomere is a structural and functional unit of muscle
tissue.

Sarcoplasmic Reticulum (SR)
• SR is an elaborate, smooth endoplasmic reticulum
– runs longitudinally and surrounds each myofibril
– Form chambers called terminal cisternae on either side
of the T-tubules
• A single T-tubule and the 2 terminal cisternae form
a triad
• SR stores Ca++
when muscle not contracting
– When stimulated, calcium released into sarcoplasm
– SR membrane has Ca++
pumps that function to pump
Ca++
out of the sarcoplasm back into the SR after
contraction

• Organization of the sarcomere
– Thick filaments = myosin filaments
• Composed of the protein myosin

• Sarcomere - repeating functional units of a myofibril
– About 10,000 sarcomeres per myofibril, end to end
– Each is about 2 µm long
• Differences in size, density, and distribution of thick and thin
filaments gives the muscle fiber a banded or striated appearance.
– A bands: a dark band; full length of thick (myosin) filament
– M line - protein to which myosins attach
– H zone - thick but NO thin filaments
– I bands: a light band; from Z disks to ends of thick filaments
• Thin but NO thick filaments
• Extends from A band of one sarcomere to A band of the next
sarcomere
– Z disk: filamentous network of protein. Serves as attachment for
actin myofilaments
– Titin filaments: elastic chains of amino acids; keep thick and
thin filaments in proper alignment

Myosin (Thick)
Myofilament
• Many elongated myosin molecules
shaped like golf clubs.
• Single filament contains roughly 300
myosin molecules
• Molecule consists of two heavy myosin
molecules wound together to form a rod
portion lying parallel to the myosin
myofilament and two heads that extend
laterally.
• Myosin heads
1. Can bind to active sites on the actin
molecules to form cross-bridges.
(Actin binding site)
2. Attached to the rod portion by a hinge
region that can bend and straighten
during contraction.
3. Have ATPase activity: activity that
breaks down adenosine triphosphate
(ATP), releasing energy. Part of the
energy is used to bend the hinge
region of the myosin molecule during
contraction

Actin (Thin)
Myofilaments
• Thin Filament: composed of 3 major
proteins
1. F (fibrous) actin
2. Tropomyosin
3. Troponin
• Two strands of fibrous (F) actin form a
double helix extending the length of
the myofilament; attached at either
end at sarcomere.
– Composed of G actin monomers
each of which has a myosin-binding
site (see yellow dot)
– Actin site can bind myosin during
muscle contraction.
• Tropomyosin: an elongated protein
winds along the groove of the F actin
double helix.
• Troponin is composed of three
subunits:
– Tn-A : binds to actin
– Tn-T :binds to tropomyosin,
– Tn-C :binds to calcium ions.

Structures of Cardiac Muscles
Cardiac muscles fibers have a single, centrally
located nucleus.
In response to a single action potential, cardiac
muscle tissue remains contracted 10-15x longer
than skeletal muscle tissue.
The long contraction is due to prolonged delivery
of ca2+
into the sarcoplasm.

Cardiac muscles cont’..
Cardiac muscle tissue has an endomysiun
and perimysium, but lacks an Epimysium.
Like skeletal muscle, cardiac muscle fibers
can undergo hypertrophy in response to an
increased workload.

Cardiac Muscle and Heart Function
• Cardiac muscle fibers are striated –
sarcomere is the functional unit
• Fibers are branched; connect to one
another at intercalated discs. The
discs contain several gap junctions
• Nuclei are centrally located
• Abundant mitochondria
• SR is less abundant than in skeletal
muscle, but greater in density than
smooth muscle
• Sarcolemma has specialized ion
channels that skeletal muscle does
not – voltage-gated Ca2+ channels
• Fibers are not anchored at ends;
allows for greater sarcomere
shortening and lengthening

How are cardiac contractions started? Cardiac conduction system
• Specialized muscle cells “pace” the
rest of the heart; cells contain less
actin and myosin, are thin and pale
microscopically
• Sinoatrial (SA) node; pace of about
65 bpm
• Internodal pathways connect SA
node to atrioventricular (AV) node
• AV node could act as a secondary
pacemaker; autorhythmic at about
55 bpm
• Bundle of His
• Left and right bundle branches
• Purkinje fibers; also autorhythmic at
about 45 bpm
ALL CONDUCTION FIBERS CONNECTED TO
MUSCLE FIBERS THROUGH GAP JUNCTIONS IN
THE INTERCALATED DISCS

Structures of Smooth Muscles
Smooth muscle tissue is usually activated
involuntarily.
Within each fiber is a single, oval,
centrally located nucleus.

Structures cont’..
• In addition to thick & thin filaments,
smooth muscle fibers also contain
intermediate filaments.

• Is innervated by autonomic nervous system (ANS)
• Visceral or unitary smooth muscle
– Only a few muscle fibers innervated in each group
– Impulse spreads through gap junctions
– Who sheet contracts as a unit
– Often autorhythmic
• Multiunit:
– Cells or groups of cells act as independent units
– Arrector pili of skin and iris of eye

Smooth Muscle Contraction: Mechanism

Smooth Muscle Relaxation: Mechanism

Physiology of Muscle Contraction
Stimulation and contraction of skeletal muscles
Skeletal muscle cells must be stimulated by
nerve impulses (by motor neuron) to contract.
One motor neuron may stimulate a few muscle
cells or hundreds of them at the same time.

Cont..
 One neuron along with all the muscle fibers it stimulates is
called a Motor unit.
 As the axon of a motor neuron enters a skeletal muscle it
divides in to branches called Axon terminals.
 Each axon terminals forms a gap junction with the
sarcolemma of a muscle fiber w/c is called Neuromuscular
junctions (NMJ).

CONT..
The gap b/n sarcolemma & axon terminal 
synaptic cleft.
Acetylcholine (Ach) is released from synaptic
vesicles of a neuron when the nerve impulse
reaches the axon terminals.

Cont…
Ach diffuses across the synaptic cleft and attaches
to receptors on the sarcolemma Na+
rush into
muscle cells  excess positive ions in the interior
of the cell which upsets the electrical condition of
the cell  Action Potential is generated and
travels over the entire length of the sarcolemma
 contraction of muscle cell results.

CONT…
Sarcomere shortens because of the increased
overlap of thin & thick filaments, the lengths
of the thin & thick filaments do not change.
The sliding of filaments & shortening of
sarcomeres in turn cause the shortening of the
muscle fibers.

CONT..
The sliding-filament mechanism of muscle
contraction occurs only when:
A) The level of calcium ions (Ca2+
) is high
enough(should be released from the
sarcoplasmic reticulum to the sarcoplasm)
B) ATP is available for active transport of Ca2+
.

Types of muscle contraction
Muscle contractions are classified as either
Isotonic, or Isometric
1. Isotonic contraction- shortening of muscle occurs
with constant amount of tension.
• Produces movement
• Used in
– Walking
– Moving any part of the body
Example: - Movement of fingers to make a fist.

Cont…
2.Isometric contraction- the length of the muscles
does not change, but the amount of
tension increases during the contraction process.
• Produces no movement
• Used in
– Standing
– Sitting
– Posture
Example: - Clenching the fist harder and harder.

Relaxation of Muscle
Two changes permit a muscle fiber to relax after
it has contracted:
I)The neurotransmitter Ach is rapidly broken down
by the enzyme Acetyl cholinesterase (AchE).
II) Calcium ions are rapidly transported from the
sarcoplasm into the sarcoplasmic reticulum.

Types of Muscles
• Prime mover – muscle with the major
responsibility for a certain movement
• Antagonist – muscle that opposes or reverses
a prime mover
• Synergist – muscle that aids a prime mover in
a movement and helps prevent rotation
• Fixator – stabilizes the origin of a prime mover

Naming&actions of Skeletal Muscles
1. Based on direction of muscle
Rectus:- have parallel fibers to the midline of the
body, eg. Rectus abdominis.
Transverse: - perpendicular fibers to the midline,
eg. Transverse abdominis.
Oblique: - fibers run diagonally, eg. External
oblique.

Cont..
2. Based on Location of muscle
Frontal: - a muscle near the frontal bone.
Tibialis anterior: - a muscle near the front
of tibia.

Cont…
3. Based on relative Size of the muscle
Maximus: - means largest, eg. Gluteus
Maximus.
Minimum: - means smallest, eg. Gluteus
minimus.

Cont…
4. Based on number of origins
Biceps: - means two origins, eg. Biceps
brachii.
Triceps: - means three origins, eg. Triceps
brachii.

Cont…
5. Based on Shape of muscle
Deltoid: - means triangular, eg. Deltoid muscle.
Trapezius: - means trapezoid, eg. Trapezius
6. Based on Origin & insertion of muscle
Sternocleidomastoid: - originates on sternum &
clavicle and inserts on mastoid process.

Cont…
7. Based on action of the muscle
Flexor - eg. Flexor carpiradialis.
Extensor- eg. Extensor carpiradialis.
Abductor- eg. Abductor policis brevis.
Adductor-eg. Adductor longus.
Rotator -moving a bone around its longitudinal axis,
eg. Obturator externus.

Pelvis, Hip, and Thigh Muscles

Superficial
Muscles:
Posterior

Most important muscles for injection administration
1.The deltoid muscle
It is a favorite injection site when a relatively
small amounts of medication <5ml must be
given IM.

cont…
2. Gluteus maximums
Superificial muscle of the hip that forms most
of the flesh of the buttock.
Powerful hip extensor that acts to bring the
thigh in a straight line with the pelvis.

Cont..
3. Gluteus medius
Is an important muscle for giving IM injection
particularly when > 5ml, which contains the
large, fleshy gluteus maximums, overlies the
large sciatic nerve.

Cont..
4. Vastus lateralis
Vastus lateralis & rectus femoris are
sometimes used as IM injection sites,
particularly in infants, who have poorly
developed gluteus muscles.

Weak places in the abdominal wall
Weak places are site where discontinuity of the
muscles found.
1.The umbilicus:-a small scar on the abdomen
that marks they former attachment of the
umbilical cord to the fetus.

Cont..
2. Inguinal canal: - An oblique canal in the lower
part of the anterior abdominal wall above the
medial part of the inguinal ligament, which is
about 4 cm in length.
3. Femoral ring: - The mouth of the femoral canal,
which is the medial compartment of the femoral
sheath.

HERNIA
 is protrusion of an organ or part of an organ
(Eg, the intestine) through the weak places in
the abdominal wall.
Types of Hernia
Umbilical hernia, diaphragmatic (hiatal)
hernia, inguinal hernia, femoral hernia etc…

Cont..
1. Diaphragmatic (Hiatal) hernia: is the
protrusion of the lower esophagus,
stomach, or intestine into the thoracic
cavity through the esophageal hiatus.

Cont…
2. Inguinal hernia: protrusion of the contents
through the inguinal canal below the inguinal
ligament.
It has two types:
A. Direct type: Bulges through the post wall of
inguinal canal.

CONT…
B. Indirect type: passes through internal
inguinal ring along the inguinal canal.
It may extend down to the scrotum.

Cont…
3. Umbilical hernia: develop at the
umbilical ring and may be present at birth
or develop gradually during the life of the
individual.
4. Femoral hernia: is a protrusion of the
content through the femoral ring.

Important terminologies
1. Hernia sac - is an out pouch of the peritoneum.
2. Content - is a viscus or any other organ inside a
sac. It can be:
Small bowel and omentum (commonest)
Large bowel appendix
The bladder

Cont..
3. Reducible hernia- when the protruded viscus can be
returned back to the abdomen.
4. Irreducible hernia- when the contents can’t be returned
back.
5. Obstructed hernia- the content of the hernia (intestine)
is occluded but no impairment of vascular supply.

Cont…
6. Strangulated hernia- when the vascularity of
protruded viscus is impaired.
7. Richter’s hernia- only one side of the wall of the
intestine is herniated. Strangulation is possible.
8. Sliding hernia- when extra peritoneal structure
form part of the wall of the sac.

QUIZE
1 Describe the function of muscle tissue?
2 Write the difference between smooth,skeletal
and cardiac muscle?
3 Describe the three connective tissue layer of sk
eletal muscel ?
4 Briefly explain four characteristics of muscular
tissue.
5 Define the following terms
sacrolemma,sacroplasm, I band, A band,H zone
and sarcomere.

Learning objectives
List the structures and basic functions
of the nervous system.
Describe the three basic functions of
the nervous system

Nervous cont’..
Introduction to the nervous
system
• The nervous system is an
intricate, highly organized
network of billions of neurons
and even more neuroglia.

Types & Structures of Nerve Cells
A nervous tissue is made up of two principal
types of nerve cells.
1. Neuron 2. Neuroglia
1. NEURONS:- are the basic information
processing units of the nervous system and it has
three parts.

Cont..
1. Cell body: - contains the nucleus and is the
metabolic centre of the cell.
2. Dendrites: - Multiple processes which conduct
electric currents (Impulses) toward the cell body.
3. Axons:-conduct nerve impulses away from the cell
body toward another neuron, a muscle fibre or a
gland cell.

Cont…
Some axons have side branches called Axon
collaterals.
The axons and axon collaterals end by
dividing in to many fine processes called Axon
Terminal.

Cont..
The sites where two neurons or a neuron and
an effectors cell can communicate are termed
as Synapses.
The tips of the axon terminals swell in to Synaptic
End Bulbs, which contain synaptic vesicles, tiny
sacs that store chemicals called Neurotransmitters.

Cont..
Majority of the axons are covered with a
whitish, fatty material, called myelin sheath.
Myelin protects and insulates the fibres and
increases transmission rate of nerve impulses.

Functionally classification of Neurons
1. Sensory (Afferent) neurons:- neurons w/c transmit
impulse from the body to CNS.
2. Motor (Efferent) neurons:- transmit impulses away
from CNS.
3. Association neurons (Interneurons) :- conduct
impulses from sensory neurons to motor neurons.
About 90% of our neuron is interneuron.

Structural classification of Neurons
Based on the number of processes extending from the
cell body:
1. Multipolar; one axon & several dendrites
2. Bipolar; one axon and one dendrite (Eg. special
sensory nerves).
3. Unipolar; dendrite emerge from terminal end of axon.

Cont…
2. NEUROGLIA
 Neuroglia are supporting and protecting cells of a nervous
tissue.
 Are smaller than neurons and 5 to 50 times more
numerous.
unlike neurons, neurolgia:
Are not able to transmit nerve impulses.
Never lose their ability to divide.

Cont…
Four types of neuroglia in CNS
1. Astrocytes; controll exchange of materials b/n
blood vessels and neuron.
2. Oligodendrocytes; produce a myelin sheath.
3. Microglia; phagocytic macrophage.
4. Ependymal cells; line ventricles (fluid filled
cavities).

Cont…
Two types of neuroglia in PNS
1. Schwann cells (neuro-lemmocytes):-
produce myelin sheath.
2. Satellite cells: - are located in ganglia
where they surround the cell bodies of
neurons.

CENTRAL NERVOUS SYSTEM (CNS)
The CNS as its name implies is centrally located.
It has two major structures: Brain and Spinal
Cord.
The brain is located in the cranial cavity of the
skull and the spinal cord is surrounded in the
vertebral column.

THE CNS PROTECTIONS & FUNCTIONS
The nervous tissue is not a strong tissue. So nature
safeguards the chief organs by three structures:
1. Meninges
2. cerebrospinal fluid
3. The bony skull & vertebrae.

Cont…
1. Meninges:- are three fluid-containing membranes
which are located beneath the bones of skull and
vertebrae surrounding the CNS.
The meninges that protect the spinal cord are
called spinal meninges, and those that protect the
brain are called cranial meninges.

Cont…
The three meningeal membranes are:
A.Dura mater:- the tough outer layer.
B.Arachnoid mater:- the membrane between the
dura & pia mater.
C.Pia-mater:-the innermost membrane that
adheres to the surface of the spinal cord &
brain.

Cont…
The space between the dura & arachnoid
mater is called subdural space, and
between the arachnoid & pia mater is
called subarachnoid space.

Cont…
2. Cerebrospinal Fluid (CSF):- is a fluid which
continuously circulates in the subarachnoid
space of the CNS, and through a cavities in the
brain known as ventricles;
2 lateral ventricles,
one third ventricle & one fourth ventricle.

Cont…
 CSF may be removed from subarachnoid space
between L3 &L4, or L4 & L5 by a spinal tap/ Lumbar
Puncture (LP).
General Indications of A spinal tap (LP);
1. To aspirate the CSF for diagnostic & therapeutic
procedures.
2. To introduce medication and anaesthetics

Cont…
3. Bony Skull & Vertebrae :- this is discussed on
the previous chapter, on the skeletal system.
Parts and functions of the Brain
The brain is the largest and most complex
mass of nervous tissue in the body.

Parts and functions of brain
Brain has four major regions:
1. Cerebral hemispheres
2. Diencephalons
3. Brain stem
4. Cerebellum

Cont…
1. Cerebral Hemispheres
 Paired , most superior part of the brain
 The entire surface exhibits elevated ridges of tissue
called gyri, separated by shallow grooves called sulci.
 Deeper grooves called fissures separate the cerebrum
in to large regions.

Cont…
The longitudinal fissure separates the
cerebrum into right & left cerebral
hemispheres.
Other fissures (central, lateral, parieto-
occipital fissures) divide each cerebral
hemisphere in to four lobes (frontal,
temporal, parietal & occipital lobes).

Cross section of cerebrum
1. Cerebral cortex:is a thin outer layer of gray matter.
Speech, evaluation of stimuli, conscious thinking,
and control of skeletal muscles.
2. Cerebral white matter underlies the cerebral cortex.
It contains mostly myelinated axons that connect
cerebral hemispheres (association fibers).

Cont…
3. Basal ganglia (basal nuclei) are several
pockets of gray matter located deep inside the
cerebral white matter.
It is involved in relaying and modifying nerve
impulses passing from the cerebral cortex to
the spinal cord.

Cont…
The somatic sensory area is located
posterior to the central fissure in the
parietal lobe (this area allows your to
recognize pain, coldness, or light touch).

Cont…
Impulses from special sense organs are
integrated in other cortical areas (e.g. visual
area in the occipital lobe, auditory area in
temporal lobe, and olfactory area deep inside
the temporal lobe).

Cont…
The primary motor area is anterior to the
central fissure in the frontal lobe.
The axons of these motor neurons form the
major voluntary motor tract -- the pyramidal or
cortico-spinal tract, which descends to the
spinal cord.

Cont….
Areas involved in higher intellectual
reasoning in the anterior part of the
frontal lobes.
Complex memories in the temporal and
frontal lobes.

Cont…
2. Diencephalons
Sits atop the brain-stem and is enclosed by the
cerebral hemispheres.
Consists three principally parts:
A. Thalamus; oval structure above midbrain.
Pain, pressure and temperature sensation centre.

Cont…
2. Epithalamus; contains pineal gland w/c secrete
melatonin
3. Hypothalamus; small part of diencephalons that lie
below thalamus and above the pituitary gland.
 It produces two hormones (ADH and oxytocin) and
various releasing hormones that control hormone
production in the anterior pituitary gland.

Cont…
3. Brain Stem
 the size of a thumb in diameter & 3 inches
long.
It connects diencephalons to spinal cord.
Consists of: Mid- brain, Pons, and Medulla
oblongata.

Cont…
A. Midbrain:
Extends from the pons to the lower portion of
the diencephalons..
The nuclei for the oculomotor and trachear
nerves originate in the mid -brain.

Cont…
B. Pons:
Below mid-brain and superior to the medulla
oblongata; anterior to the cerebellum.
The nuclei for some cranial nerves originate in
the pons.
It have nuclei that help to regulate breathing.

Cont…
C. Medulla oblongata:
The most inferior part of the brain stem.
It controls: Heart rate, Blood pressure,
Breathing, swallowing, vomiting, etc.
It merge with spinal cord at foramen magnum.

Cont…
RETICULAR FORMATION;-a diffuse mass of
grey matter interspersed within the white matter of
the brain stem.
Sensory function - alerting the cerebral cortex to
incoming sensory signals.

Cont..
Motor function - helps regulate muscle tone.
RAS (reticular activating system)- plays a role
in alertness and filtering out unimportant
sensory information.

Cont…
4. CEREBELLUM
lies under the occipital lobe of a cerebrum.
Has two hemispheres, a convoluted
surfaces(folia).
Provides the precise timing for skeletal muscle
activity and controls our balance and equilibrium.

PARTS AND FUNCTIONS OF SPINAL CORD
The spinal cord is about 45 cm in length and 2
cm in diameter in adults.
It is the major reflex centre and enclosed
within the vertebral column.
Extends from the foramen magnum of the
skull to the 1st
or 2nd
lumbar vertebra.

Cont…
A cross section of the spinal cord reveals the
following features:
1. Ventral root (anterior or motor root) contain
motor nerve axons.
2. Dorsal root (posterior or sensory root) contain
sensory nerve fibers.

Cont…
Functions of spinal cord:
1.Electrical communication
2.Walking (locomotion)
3.Reflexes-predictable involuntary responses to
stimuli.

PERIPHERAL NERVOUS SYSTEM (PNS)
 The PNS consists of nerves and scattered of neuronal cell
bodies (ganglia) found out side the CNS.
Somatic NS Parasympathetic
PNS Autonomic NS Sympathetic

cont…
Cranial nerves
 The 12 pairs of cranial nerves are so named because they
pass through various foramina in the bones of the cranium
and arise from the brain inside the cranial cavity.
 It primarily serve the head & neck.
 Only one pair (Vagus nerve) extends to the thoracic
and abdominal cavities.

Cont…
 Three cranial nerves (I, II and VIII) carry axons of
sensory neurons and thus are called special sensory
nerves.
 Five cranial nerves (III, IV, VI, XI, and XII) are
classified as motor nerves.
 The remaining (V, VII, IX, and X) are mixed nerves.

Cont…
Spinal nerves; Serve neck, trunk & limbs.
 8 pairs of cervical nerves (C1-C8)
12 pairs of thoracic nerves (T1-T12)
5 pairs of lumbar nerve (L1-L5)
5 pairs of sacral nerves (S1-S5)
1 pair of coccygeal nerves (Co1)

AUTONOMIC NERVOUS SYSTEM ( ANS)
It composed of special group of neurons that
regulate :-
1. Cardiac muscle ( The heart)
2. Smooth muscles ( found in the walls of
visceral organs and blood vessels )
3. Glands

Cont…
ANS Has two divisions and the division differ in
anatomy &function but they often innervate the
same organ & may have cooperative or contracting
effect on them.
1. Sympathetic division
2. Parasympathetic division

Cont…
A. Sympathetic Division
Has short preganglionic &long post ganglionic
fibers.
The first (preganglionic) Neuron cell bodies are in
the Gray matter of the spinal cord from T1
through L2. Hence, also called the thoraco-
lumbar division.

Cont…
B. Parasympathetic division- its preganglionic neurons
are located in the pons, medulla oblongata, segment s2 to
s4 of the spinal cord
The first (preganglionic) neuron cell bodies are located
in brain nuclei of several cranial nerves and in the S-2
through S-4 level of the spinal cord, hence, also called
cranio-sacral division.

INTRODUCTION…
 Sensation is the conscious or subconscious awareness
of external or internal conditions of the body.

Cont…
For Sensation to occur, four conditions must be satisfied:
 a stimulus or change in the environment
 a sensory receptor must convert the stimulus to an
electrical signal
 conduction of a nerve impulse
 Reception and integration of the nerve impulse into a
sensation.

Cont….
Sensations can be grouped into two classes:
A.General senses: somatic senses, and visceral senses.
Somatic – tactile, thermal, pain.
Visceral – conditions within body fluid and
internal organs.
B.Special senses: smell, taste, vision, hearing and
equilibrium (balance).

The Eye
Eyes are very complex organs that collect
visual information that is transmitted to the
brain via the optic nerve.

External and accessory organs of the eye
1.The extrinsic eye muscles,
2.Eye lids, eye lashes and eye brows,
3.Conjunctiva, and
4.Lacrimal apparatus.

Cont..
The lacrimal apparatus consists of:
1. Lacrimal gland,  Releases a tear (diluted salt
solution)
2. Lacrimal ducts
3. Lacrimal canals  Drain lacrimal secretion.
4. Lacrimal sacs,
5. Nasolacrimal duct

Cont…
Lacrimal secretion:
Contains antibodies and lysozymes that
destroy bacteria (i.e. it cleanses and protects
the eye surface).
Moistens and lubricates the eye surface.

Extrinsic Muscles of the Eye & Its Functions
Name of muscle Cranial nerve Actions
Lateral rectus(LR) VI (Abducens) Moves the eye laterally(Abduction)
Medial
rectus(MR)
III
(Oculomotor)
Moves the eye medially(Adduction)
Superior
rectus(SR)
III
(Oculomotor)
Elevates eye or rolls it superiorly
Inferior rectus(IR) III
(Oculomotor)
Depresses eye or rolls it inferiorly
Inferior
oblique(IO)
III
(Oculomotor)
Elevates eye and turns it laterally
(Extortion)
Superior
oblique(SO)
IV (Trochlear) Depresses eye and turns it medially
(Intortion)

Cont….
SO4LR6 : all extrinsic eye muscles are
innervated by cranial nerve-III
(oculomotor), except the Superior oblique
and lateral rectus muscles

Eye ball and its layers
Anatomically, the wall of the eyeball consists
of the following three layers:
1.Fibrous tunic; is the superficial layer of the
eyeball and consist of the anteriorly cornea
and posteriorly sclera.

Cont….
A. Cornea: non-vascular, transparent coat that
covers the colored iris and It help to focus the
light onto the retina.
B. Sclera: the “white of the eye”.
It protects its inner parts and serves as a site of
attachment for extrinsic eye muscle.

Cont…
2. Vascular tunic; is the middle layer of the eye
ball.
Posteriorly the choroid which is highly
vascularized, and anteriorly the ciliary body
and iris.

Cont…
3. Sensory tunic (retina)
The inner most layer of the eye ball.
It is the beginning of the visual pathway.
The retina contains millions of photoreceptor
cells-Rods (120million) and Cones (6million).

Cont…
The eye is connected to the brain through the
optic nerve.
The point of connection of eye with the brain
is called the "blind spot" because it is
insensitive to light.

Cont…
Lens
Resembles the lens of a camera and focuses
the light, changing shape as it takes in light
reflected from objects near and far.
The interior of the eye is filled with fluids
called humors that help maintain its shape.

Cont…
The lens divides the interior of the eyeball into
two cavities.
1. The anterior cavity filled with aqueous humor.
2. A posterior cavity called vitreous chamber
filled with vitreous humor or vitreous body.

The Ear
Ear is the organ concerned with hearing and it has
three parts: the outer ear, the middle ear and the
inner ear.
Outer and middle ear structures are involved
with hearing only whereas the inner ear
functions in both equilibrium and hearing.

The auditory apparatus
A. Outer (External) Ear
The external auditory canal skin lined walls
have ceruminous glands which secrete a waxy
yellow substance called cerumen, or ear wax.
Ends at the tympanic membrane or ear drum
which separates the outer from the middle ear.

Cont….
B. Middle Ear: also called tympanic cavity.
Small air filled cavity within the temporal
bone.
The Auditory tube (Eustachian tube) runs
obliquely downward to link the middle ear
cavity with the throat.

Cont…..
The tympanic cavity is spanned by three
smallest bones in the body (ossicles).
C. Internal Ear/ Inner Ear:
Is fluid-filled cavity which is divided into an
outer bony labyrinth and inner membranous
labyrinth.

Cont…
The bony labyrinth has three subdivisions:
1.Cochlea  sense organ for hearing
2.Vestibule Sense organ for
3.Semicircular canals equilibrium & balance

Mechanism of hearing
Impulses from the hearing and equilibrium
receptors of the inner ear are transmitted to the
brain via the Vestibulocochlear nerve.
Hearing is the last sense to leave our
awareness and the first to return.

The Nose
The nose, along with the mouth, lets air in and
out of the body.
The cavity of the nose is lined with mucous
membranes that contain 10 million to 100
million of smell (olfactory) receptors.

cont…..
Nose gets blood supply from the facial artery.
Olfactory impressions are long lasting and very
much a part of our memories and emotions.
The sense of smell is sometimes temporarily lost
when a person has a cold.

The Tongue
Is a muscular organ in the mouth which is
covered with moist, pink tissue called
mucosa and tiny bumps called papillae.

Cont…
 Teste buds are able to detect four basic tastes: salty,
sweet, bitter, and sour.
 Women, in general, have a greater number of taste buds
than men.
 The specific cells that respond to chemicals dissolved
in the saliva are epithelial cells called gustatory cells.

Cont….
Gustatory Receptor Cells On The Tongue:
Sweet receptors tip of tongue(At apex).
Salty receptors side-tip of tongue
(Anterolateral).
Bitter receptors posterior portion of tongue.
Sour receptors lateral areas of the tongue.

Cont…
Cranial nerves (VII, IX, X) carry taste impulses
from the various taste buds to the gustatory cortex.
The Facial nerve (VII) serves the anterior part of
the tongue.
The other two cranial nerves serve the other taste
bud containing areas.

Cont…
Classification of tongue muscles:
1. External Tongue muscles: used to move the tongue
for speech & they manipulate food and all are
supplied by CN-XII.
2. Intrinsic Muscles of the Tongue: Consists of four
muscles which act to alter the shape but not position
of the tongue.

Introduction to Endocrine System
Endocrine system is made up of glands that
produce and secrete hormones,
Hormones are chemical substances produced
in the body that regulate the activity of cells or
organs.

Cont…
 The endocrine system's effects are slow to initiate,
and prolonged in their response, lasting from a few
hours up to weeks.
 The nervous system sends information very quickly,
and responses are generally short lived.
 In vertebrates, the hypothalamus is the neural control
centre for all endocrine systems.

Comparison of the endocrine system and nervous system
Feature Endocrine system Nervous system
Overall function Maintain homeostasis Maintain homeostasis
Control Virtually all tissue Muscles and glandular tissue
only
Effectors cell Target cells (throughout the
body )
In muscle and glandular cells
only
Chemical messenger Hormone Neurotransmitter
Secreted by Glandular epithelial cells Neurons
Distance travel Long(by way of circulating
blood)
Short(across microscopic
synapse)
Speed & action duration Slow to appear long lasting
effect.
Fast, short lived

CONT…
Hormones:
Hormones are chemical messengers created by
the body.
They transfer information from one set of cells
to another to coordinate the functions of
different parts of the body.

CONT….
Hormones chemically fall in two categories:
1) Proteins: All hormones except those of
adrenal cortex & the sex glands are proteins.
2) Steroids: are hormones derived from lipids &
produced by the adrenal cortex & sex glands.

Cont..
Glands of body are composed predominantly
of epithelial tissue, which are of two types:
1.Endocrine glands: its secretions have
intracellular effect.
2.Exocrine glands: its secretions have extra
cellular effect such as digestion of food.

Comparison: Endocrine v. Exocrine
 Endocrine glands
 Secretions enter interstitial
fluid and then 
bloodstream
 Stay in the body: endo-
 Examples: all hormones
such as growth hormone,
insulin, adrenalin, estrogen,
testosterone
 Exocrine glands
 Secrete substances that
enter ducts
 Ultimately exit the body
(exo-)
 Examples: mucus, saliva
and other digestive
secretions, sweat, tears

Cont…
The major endocrine glands include the pineal
gland, pituitary gland, pancreas, ovaries, testes,
thyroid gland, parathyroid gland, hypothalamus,
and adrenal glands.

1.Pituitary Gland:
• It is known as the master gland and also called
hypophysis.
• Located in depression in sphenoid bone just inferior
to the brain.
 It has two separate divisions:
A. Anterior pituitary(Adeno-hypophysis):It is connected by
blood vessels called hypothalamo-hypophyseal portal
system.

Cont..
 The Anterior lobe basically secrets six hormones,
these are GH, TSH, FSH, LH, ACTH , Prolactin
(PRL) and MSH.

1. Human Growth Hormone (hGH)
• hGH promotes synthesis of insulinlike growth
factors (IGFs) = somatomedins
– Secreted by liver, muscle, cartilage, bone cells
– Actions of IGFs much like those of insulin
• Regulation
– By hypothalamic hormones
• Growth hormone-releasing hormone (GHRH)
• Growth hormone-inhibiting Hormone (GHIH )
– By blood glucose levels
• Low blood glucose levels  release of GHRH

• Actions of hGH
– Stimulates protein synthesis
• Maintains muscle and bone mass
• Promotes healing of injuries, tissue repair
– Makes “fuel” (ATP) available for growth
• Causes fat breakdown (“baby fat”) and release of fatty
acids into blood
• Breaks down liver glycogen  releases glucose into
blood

2. Thyroid-Stimulating Hormone (TSH)
• Stimulates the formation and secretion of
thyroid hormones (T3, T4) by thyroid gland
• Regulation of TSH (negative feedback)
– Low blood levels of T3, T4 
– Hypothalamus  Thyrotropin-releasing hormone
(TRH) 
– TRH stimulates release of TSH
– TSH stimulates thyroid production of T3, T4

• In females
– FSH starts follicle development 
• Starts egg production
• Starts estrogen production from follicle cells
– LH stimulates formation of corpus luteum
• Completion of egg and its ovulation
• Secretion of progesterone + estrogen
• In males
– FSH  sperm production in testes
– LH  release of testosterone from testes
3 Follicle Stimulating Hormone (FSH)
and Luteinizing Hormone (LH)

• Regulation (feedback mechanisms)
– Gonadotrophin-releasing hormone (GnRH) from
hypothalamus  release of FSH or LH from
anterior pituitary
– FSH  increases estrogen in females
– LH  increases estrogen (E) and progesterone (P)
in females and testosterone (T) in males
– High levels of these ovarian or testicular
hormones (E, P, and T) suppress production of
GnRH

5. Prolactin (PRL)
• Initiates and maintains milk production by
mammary glands
– Ejection of milk depends on oxytocin
• Regulation
– Prolactin inhibiting hormone (PIH) suppresses
prolactin release
– High levels of estrogens PRH  prolactin release
• Unknown function in males
– Hypersecretion  erectile dysfunction

6. Adrenocorticotropic Hormone
(ACTH)
• Controls production and secretion of
glucocorticoids from adrenal cortex
• Regulation of ACTH
– Corticotrophin releasing hormone (CRH) from
hypothalamus stimulates secretion of ACTH
– Stress-related stimuli can also stimulate ACTH
release
– Glucocorticoids inhibit CRH and ACTH release

7. Melanocyte Stimulating Hormone (MSH)
• Small amounts in bloodstream
• Excess amounts causes skin darkening

Posterior Pituitary
• Hormones made in hypothalamus pass down
axons to posterior pituitary
– Nerve impulses there cause release of hormones
• Two hormones released
– Oxytocin causes
• Smooth muscle contraction of uterus during childbirth
• Causes “letdown” of milk from glands to ducts
• Some sexual pleasure during sexual activity

Posterior Pituitary
– Antidiuretic Hormone (ADH) = vasopressin
• Causes kidneys to retain more water
• Causes vasoconstriction  increases blood pressure
• Dehydration, pain, stress  increase ADH secretion

Osmoreceptors
High blood osmotic
pressure stimulates
hypothalamic
osmoreceptors
1
Osmoreceptors
High blood osmotic
pressure stimulates
hypothalamic
osmoreceptors
Osmoreceptors
activate the
neurosecretory cells
that synthesize and
release ADH
Hypothalamus
1
2
Osmoreceptors
High blood osmotic
pressure stimulates
hypothalamic
osmoreceptors
Nerve impulses
liberate ADH from
axon terminals in
the posterior
pituitary into
the bloodstream
Osmoreceptors
activate the
that synthesize and
release ADH
Hypothalamus
ADH
1
2
3
Osmoreceptors
High blood osmotic
pressure stimulates
hypothalamic
osmoreceptors
Nerve impulses
liberate ADH from
axon terminals in
the posterior
pituitary into
the bloodstream
Osmoreceptors
activate the
that synthesize and
release ADH
Hypothalamus
Sudoriferous
(sweat) glands
decrease water
loss by perspiration
from the skin
Arterioles constrict,
which increases
blood pressure
Kidneys retain
more water,
which decreases
urine output
ADH
Target tissues
1
2
3
4
Osmoreceptors
High blood osmotic
pressure stimulates
hypothalamic
osmoreceptors
Low blood osmotic
pressure inhibits
hypothalamic
osmoreceptors
Nerve impulses
liberate ADH from
axon terminals in
the posterior
pituitary into
the bloodstream
Osmoreceptors
activate the
that synthesize and
release ADH
Hypothalamus
Sudoriferous
(sweat) glands
decrease water
from the skin
which increases
blood pressure
Kidneys retain
more water,
which decreases
urine output
ADH
Target tissues
1
2
3
4
5
Osmoreceptors
High blood osmotic
pressure stimulates
hypothalamic
osmoreceptors
Low blood osmotic
pressure inhibits
hypothalamic
osmoreceptors
Nerve impulses
liberate ADH from
axon terminals in
the posterior
pituitary into
the bloodstream
Osmoreceptors
activate the
that synthesize and
release ADH
Hypothalamus
Inhibition of osmo-
receptors reduces or
stops ADH secretion
Sudoriferous
(sweat) glands
decrease water
from the skin
which increases
blood pressure
Kidneys retain
more water,
which decreases
urine output
ADH
Target tissues
1
2
3
4
5
6
ADH
Regulation

Cont….
It is the largest endocrine gland having blood
supply by superior thyroid artery.
Situated at the base of the throat just inferior to
the Adam’s apple.
Has two lobes (right and left) joined by the
thyroid isthmus.

Cont…
It synthesize two hormones:
Thyroxine (T4) and Tri-iodothyronine (T3);
Stimulate metabolism of all cells & cell growth.
Control the rate at w/c glucose is burned or
oxidized and converted to body heat and
chemical energy.

Thyroid Hormones: Actions
• T4 (thyroxine) and T3 increase basal metabolic
rate, protein synthesis, and growth
– Blood level is controlled by TRH and TSH
– Increase in the body’s demand for ATP can also
raise blood levels
• Calcitonin inhibits osteoclasts
– Inhibits osteoclasts. Effects:
• Strengthens bones
• Decreases blood Ca2+
– Feedback control based on Ca2+
blood levels

Cont…
Abnormal conditions of Thyroid Gland:
Hyperthyroidism: ed TH
 Hypothyroidism:  ed TH
Goiter is the condition in w/c the thyroid gland is
unable to produce T4 & T3 due to low level of TSH.

Low blood levels of T3
and T3 or low metabolic
rate stimulate release of
Hypothalamus
TRH
Actions of Thyroid Hormones:
Increase basal metabolic rate
Stimulate synthesis of Na+
/K+
ATPase
Increase body temperature (calorigenic effect)
Stimulate protein synthesis
Increase the use of glucose and fatty acids for ATP production
Stimulate lipolysis
Enhance some actions of catecholamines
Regulate development and growth of nervous tissue and bones
1
Anterior
pituitary
TRH, carried
by hypophyseal
portal veins to
anterior pituitary,
stimulates
release of TSH
by thyrotrophs
Hypothalamus
TSH
TRH
/K+
ATPase
Stimulate lipolysis
1
2
Anterior
pituitary
TRH, carried
by hypophyseal
portal veins to
anterior pituitary,
stimulates
release of TSH
by thyrotrophs
TSH released into
blood stimulates
thyroid follicular cells
Thyroid
follicle
Hypothalamus
Anterior
pituitary
TSH
TRH
/K+
ATPase
Stimulate lipolysis
1
2
3
T3 and T4
released into
blood by
follicular cells
TRH, carried
by hypophyseal
portal veins to
anterior pituitary,
stimulates
release of TSH
by thyrotrophs
TSH released into
blood stimulates
Thyroid
follicle
Hypothalamus
Anterior
pituitary
TSH
TRH
/K+
ATPase
Stimulate lipolysis
1
2
3
4 T3 and T4
released into
blood by
follicular cells
Elevated
T3inhibits
release of
TRH and
TSH
(negative
feedback)
TRH, carried
by hypophyseal
portal veins to
anterior pituitary,
stimulates
release of TSH
by thyrotrophs
TSH released into
blood stimulates
Thyroid
follicle
Hypothalamus
Anterior
pituitary
TSH
TRH
/K+
ATPase
Stimulate lipolysis
1
2
3
5
4
Thyroid Hormone
Regulation

3. Parathyroid Glands
 They are four in number, are embedded in the dorsal
surface of the thyroid gland.
 Secret parathyroid or pararthormone (PTH) in
response to low plasma calcium.
 Blood calcium level directly controls the secretion of
both calcitonin and parathyroid hormone.

Cont….
It acts on bone & kidney:
 Cause demineralization of bone to elevate plasma
calcium & phosphate levels.
 Cause phosphate to be secreted by urine.
 Cause increased intestinal absorption of calcium by
stimulating the kidney to produce active vitamin D,
w/c increase calcium absorption in gut.

Copyright 2010, John Wiley & Sons, Inc.
1 High level of Ca2+
in blood
stimulates thyroid gland
parafollicular cells to
release more CT.
in blood
release more CT.
CALCITONIN inhibits
osteoclasts, thus decreasing
blood Ca2+
level.
2
in blood
release more CT.
Low level of Ca2+
in blood
stimulates parathyroid
gland chief cells to release
more PTH.
CALCITONIN inhibits
blood Ca2+
level.
3
2
in blood
release more CT.
Low level of Ca2+
in blood
more PTH.
CALCITONIN inhibits
blood Ca2+
level.
PARATHYROID HORMONE (PTH)
promotes release of Ca2+
from
bone extracellular matrix into
blood and slows loss of Ca2+
in urine, thus increasing blood
Ca2+
level.
3
4 2
1
PTH also stimulates
the kidneys to release
CALCITRIOL.
High level of Ca2+
in blood
release more CT.
Low level of Ca2+
in blood
more PTH.
CALCITONIN inhibits
blood Ca2+
level.
from
Ca2+
level.
3
4 2
5
1
CALCITRIOL stimulates
increased absorption of
Ca2+
from foods, which
increases blood Ca2+
level.
PTH also stimulates
the kidneys to release
CALCITRIOL.
High level of Ca2+
in blood
release more CT.
Low level of Ca2+
in blood
more PTH.
CALCITONIN inhibits
blood Ca2+
level.
from
Ca2+
level.
3
4 2
5
6
Calcium Regulation

4. Adrenal (Suprarenal) Glands

Cont…
Adrenal glands are paired yellowish masses,
situated at superior poles of each kidney.
Each glands consisting of two distinct entities:
1. Adrenal cortex: outer part.
2. Adrenal medulla: inner part

Cont……
Adrenal cortex consists the ffg three zones:
A. Thin outer zona glomerulosa which secrete
mineralocorticoids.
B. Thick middle zona fasciculata secrete mainly
glucocorticoid.
C. Inner zona reticularis bordering on the medulla
synthesize small amounts of weak androgens.

Cont…
Adrenal medulla: Composed of neuron-secretary
tissue, that secret the catecholamine hormones
epinephrine and norepinephrine.
Adrenal cortex: Produce three major groups of
hormone collectively referred to as corticosteroid.

5. The Pancreas/ islet of Langerhans
The pancreas is one of abdominal cavity organs
that lie behind the stomach to the left lateral to
duodenum.
Its endocrine functions is performed by the islets
of langarhans.
It is composed of endocrine & exocrine tissues.

Cont…
Exocrine tissue: Secretes a serious containing
fluid; digestive enzyme (pancreatic juice).
It releases its secretion through ducts w/c drain
directly into part of small intestine (duodenum).

Cont….
Endocrine tissue contains:
Alpha cells: secrete glucagon;es blood glucose.
Beta cells: secrete insulin; es blood glucose.
Delta cells: secrete somatostatin.
Pancreatic poly peptide (PP) cells also influence
digestion & distribution of food molecule.

Low blood glucose
(hypoglycemia)
stimulates alpha
cells to secrete
1
GLUCAGON
Glucagon acts on
hepatocytes
(liver cells) to:
• convert glycogen
into glucose
(glycogenolysis)
• form glucose from
lactic acid and
certain amino acids
(gluconeogenesis)
Low blood glucose
(hypoglycemia)
stimulates alpha
cells to secrete
GLUCAGON
1
2 Glucagon acts on
hepatocytes
(liver cells) to:
into glucose
(glycogenolysis)
lactic acid and
certain amino acids
(gluconeogenesis)
Glucose released
by hepatocytes
raises blood glucose
level to normal
Low blood glucose
(hypoglycemia)
stimulates alpha
cells to secrete
GLUCAGON
1
2
3
Glucagon acts on
hepatocytes
(liver cells) to:
into glucose
(glycogenolysis)
lactic acid and
certain amino acids
(gluconeogenesis)
Glucose released
by hepatocytes
level to normal
If blood glucose
continues to rise,
hyperglycemia inhibits
release of glucagon
Low blood glucose
(hypoglycemia)
stimulates alpha
cells to secrete
GLUCAGON
1
2
3
4
Glucagon acts on
hepatocytes
(liver cells) to:
into glucose
(glycogenolysis)
lactic acid and
certain amino acids
(gluconeogenesis)
Glucose released
by hepatocytes
level to normal
If blood glucose
continues to rise,
release of glucagon
Low blood glucose
(hypoglycemia)
stimulates alpha
cells to secrete
High blood glucose
(hyperglycemia)
stimulates beta cells
to secrete
GLUCAGON
1 5
2
3
4
INSULIN
Insulin acts on various
body cells to:
• accelerate facilitated
diffusion of glucose
into cells
• speed conversion of
glucose into glycogen
(glycogenesis)
• increase uptake of
amino acids and increase
protein synthesis
• speed synthesis of fatty
acids (lipogenesis)
• slow glycogenolysis
• slow gluconeogenesis
Glucagon acts on
hepatocytes
(liver cells) to:
into glucose
(glycogenolysis)
lactic acid and
certain amino acids
(gluconeogenesis)
Glucose released
by hepatocytes
level to normal
If blood glucose
continues to rise,
release of glucagon
Low blood glucose
(hypoglycemia)
stimulates alpha
cells to secrete
High blood glucose
(hyperglycemia)
to secrete
INSULIN
GLUCAGON
1 5
2
3
4
6 Insulin acts on various
body cells to:
into cells
(glycogenesis)
protein synthesis
acids (lipogenesis)
Blood glucose level falls
Glucagon acts on
hepatocytes
(liver cells) to:
into glucose
(glycogenolysis)
lactic acid and
certain amino acids
(gluconeogenesis)
Glucose released
by hepatocytes
level to normal
If blood glucose
continues to rise,
release of glucagon
Low blood glucose
(hypoglycemia)
stimulates alpha
cells to secrete
High blood glucose
(hyperglycemia)
to secrete
INSULIN
GLUCAGON
1 5
2
3
4
6
7
Insulin acts on various
body cells to:
into cells
(glycogenesis)
protein synthesis
acids (lipogenesis)
If blood glucose continues
to fall, hypoglycemia
inhibits release of
insulin
Blood glucose level falls
Glucagon acts on
hepatocytes
(liver cells) to:
into glucose
(glycogenolysis)
lactic acid and
certain amino acids
(gluconeogenesis)
Glucose released
by hepatocytes
level to normal
If blood glucose
continues to rise,
release of glucagon
Low blood glucose
(hypoglycemia)
stimulates alpha
cells to secrete
High blood glucose
(hyperglycemia)
to secrete
INSULIN
GLUCAGON
1 5
2
3
4
6
7
8
Glucose/
Insulin
Regulation

6. Reproductive Glands
Testes: paired organs with in the scrotum of
males and composed of somniferous tubules &
interstitial cells.
It Secret androgen (testosterone).

Cont…
Ovaries: primary paired sex organs in the female
that secrete two hormones:
Estrogen: promote maintenance & dev’t of female
20
sexual characteristics.
Progesterone: promote growth of uterine lining for
successful pregnancy.

Placenta (Temporary gland)
Placenta
It is temporary organ formed in the uterus of
pregnant women.
During early pregnancy, it produces a hormone
called Human Chorionic Gonadotrophin
(HCG) hormone.

7.Pineal gland (third eye):
Small, cone-shaped gland, which lies in the
roof of the 3rd
ventricle of the brain, at the
Epithalamiums.
Is member of the nervous system and also is a
member of the endocrine system.

8.Thymus:
Located on the upper thorax posterior to the
sternum, just above the heart.
It is most active before birth & early in life, its
size is larger in infants & children & decrease
during adulthood.

Cont…
Thymus produce a hormone called thymosin,
thymic humoral factors (TF), and
thymopoietin those promote maturation of T-
cells.
T-lymphocytes helps to protect the body
against foreign organisms.

Chapter seven: Cardiovascular system
7.1 Introduction to cardiovascular system
byb

CVS..cont’..
The CVS is the transport system of the body
by which nutrients, oxygen, water & all other
essentials are carried to the tissue, cells & their
waste products are carried away.

Cont…
The circulatory system consists of two major
subdivisions:
1. The cardiovascular system which consists of the blood,
the heart & the blood vessels.
2. The lymphatic system which is a pump-less system of
vessels that aids the cardiovascular system in its function.

1.Blood
 Blood is a viscous (thick) fluid that varies in color
from bright to dark red, depending on the amount of
oxygen it contains.

Cont…
Functions of blood:
Transportation: it transports oxygen, nutrient,
carbon dioxide and other wastes.
Regulation: circulating blood helps maintain
homeostasis of all body fluid.
Protection: several types of blood proteins help
protect against disease in variety of ways.

Physical characteristics of whole blood
Denser and more viscous than water.
Its average temperature is about 380
c.
Its PH is slightly alkaline (7.35 to 7.45).
It constitutes about 8% of the total body weight.
In an average sized adult, the volume of blood is:
5-6 liters in male & 4-5 liters in females.

Cont…
Components of whole blood
1. The liquid portion called plasma (55%).
2. Cells and cell fragments called formed elements or corpuscles
(45%):
 RBCs (erythrocytes) cover 99% (4.8 – 5.4 million/mm3
of blood).
 WBCs (leukocytes) and Platelets (thrombocytes) occupy <1% of
the formed elements.

Cont….
1. Plasma:
Blood plasma is about 91.5% water and 8.5% are
solutes.
Hepatocyte (liver cells) synthesizes most of the
plasma proteins which includes the albumins (54%
of plasma proteins), globulins (38%) and
fibrinogen (7%).

Cont…
The plasma protein includes the following:
1. Albumins: Help to maintain proper blood oncotic pressure.
2. Globulins: Include antibodies or immunoglobulin that
combat infection.
3. Fibrinogen: A key protein in the formation of blood clots.
4. Complement: A system of enzymes that helps antibodies
in their fight against pathogens.

CONT…
2. Formed elements:
Red Blood cells (erythrocytes)
 RBCs are biconcave discs.
 The mature RBCs, that found in the circulating blood
does not have a nucleus.
 They contain a red pigment called hemoglobin, which
is responsible for the red color of blood.

Cont…
Function
RBCs carry oxygen from the lungs to the tissues.
They also play a role in acid base balance.
RBCs also carry a small amount of co2 from the
tissues to the lungs for elimination in exhalation.

cont..…..
 An excessive or abnormal increase in the number of
erythrocytes (RBCs) is called polycythemia.
Causes of polycythemia:
Bone marrow cancer (polycythemia):
A normal physiological response to living at high
altitude where the air is thinner and less oxygen is
available (secondary polycythemia).

Cont…
 A decrease in the oxygen carrying ability of the blood whatever the
reason, is called Anemia.
Causes of Anemia:
 Sudden hemorrhage.
 Hemolysis (destruction) of RBCs.
 Depression (destruction) of bone- marrow.
 Lack of iron in diet or due to slow (prolonged) bleeding.
 Genetic defect which leads to abnormal hemoglobin.

CONT….
RBC life span and total count
RBCs live only about 120 days. Worn-out RBCs are
phagocytized by macrophages in the spleen, liver
and bone marrow.
There are normally about 4.8 to 5.4 million RBCs
per mm3
of blood (48% to 54% of total blood
volume).

Cont…..
White blood cells (leukocytes)
They have nuclei and do not contain
Hemoglobin.
They lend to be colorless.
They are classified as: Granular and Agranular
leukocytes.

Cont…
Functions of WBCs
Most important function is to destroy pathogen
(disease causing microorganisms) by
phagocytosis and by producing antibodies (i.e.
they are important to body defense against
disease).

Cont….
WBC life span and number
 Most WBCs live only a few days. During a period of
infection many WBCs live only a few hours. However
some B & T-lymphocytic cells remain in the body for
years.
 WBC are far less numerous than RBCs. On average,
there are 4000 to 11, 000 WBCs per mm3
.

Cont…
Platelets (thrombocytes)
It is the smallest of all the formed elements.
Not cells by themselves, but fragment of cells.
Total number: 200,000 to 400,000 per mm3
.

Cont…
Function:
Platelets are essential to blood coagulation
(clotting).
Life span:
5 to 9 days after this, they are removed by
macrophages in the spleen and liver.

Cont…..
Blood cell formation (Hematopoiesis)
Blood cell formation, or hematopoiesis, occurs
in red bone marrow or myeloid tissue.
In adults, this tissue is found chiefly in flat
bones of the skull, pelvis, the ribs, sternum and
proximal epiphyses of the humerus and femur.

Cont…
The production of blood cells is controlled by
hormones, such as:
1.Erythropoietin---controls erythrocyte (RBC)
production.
2.Colony stimulating factors--- control leukocyte
(WBC) production.
3.Thrombopoietin -- accelerates platelet production.

Cont….
Blood clotting
Blood clotting or, coagulation is a protective
response that prevents blood loss when a blood
vessel is ruptured by an injury.

Cont….
Basically the clotting process consists of the following essential
steps:
1.The injured tissues release thromboplastin.
2. Thromboplastin form prothrombin.
3. Prothrombin forms thrombin.
4. Thrombin, converts soluble fibrinogen in to insoluble fibrin.
5. Fibrin forms a network of threads that entraps RBC & platelets
to form a clot.

Cont…
Clotting in an unbroken blood vessel is called
Thrombosis. The clot itself is called a
thrombus.
A blood clot, bubble of air, fat from broken
bones, or a piece of debris transported by the
blood stream is called an Embolus.

Cont….
Because emboli often formed in veins,
where blood flow is slower, the most
common site for the embolus to become
lodged is in the lungs, a condition called
pulmonary embolism.

Cont…
Blood Groups
 Based on the types of antigen present on the red blood cells, there are
four blood types (Groups);
1. Blood type A- In people whose RBCs contain only antigen A.
2. Blood type B- In people whose RBCs contain only antigen B.
3. Blood type AB- In people whose RBCs contain both A & B antigens.
4. Blood type O -Neither antigen A nor antigen B.

Cont…
In addition to antigens on RBCs, blood plasma
usually contains antibodies or agglutinins that react
with the A or B antigens if the two are mixed.
These are:-
I. Anti A antibody- reacts with antigen A
II.Anti B antibody- reacts with antigen B

The ABO Blood group system
Blood
Type
RBC
Antige
n
Plasma
Antibody
Can
receive
blood from
Can donate
blood to
Summary
A A Anti B A,O A, AB
B B Anti A B,O B, AB
AB AB None AB,A,B,O AB Universal
recipients’
O O Anti A, Anti
– B
O O,A,B,AB Universal donors’

Cont….
The Rh factor
 The Rh factor is another RBC antigen that determines
the blood group, so named Rh; b/c it was first found
in the blood of the Rhesus monkey.
 Individuals whose RBCs have the Rh antigen are said
to be Rh positive (Rh+) and those who lack this
antigen are said to be RH negative (Rh-
).

Cont….
 It can causes Erythroblastosis foetalis (hemolytic
disease of the new born) if the mother has Rh+
antibodies.
 Erythroblastosis foetalis may be prevented by
administration of immunoglobulin D (Igd) or Rho
GAM to the mother with in 72 hrs after the delivery
of Rh+ first foetus.

Cont…
HEART
The heart is a muscular pump that drives the
blood through the blood vessels.
The scientific study of normal heart and the
diseases associated with heart is Called
Cardiology.

• A dual pump that drives blood in two serial circuits, the
systemic and pulmonary circulations, and receives blood from
the rest of the body through the venae cavae.
• Pulmonary circulation - carries blood between the heart and
the lungs.
• Systemic circulation - carries blood between the heart and
the organ systems.
429
Systemic circulation:
Starts in the LV→ Aorta → Systemic arteries
→Systemic capillaries →Veins →SVC & IVC →ends
in RA
• Pulmonary circulation:
Starts in the RV →Pulmonary trunk →Pulm. arteries
→ Pulm capillaries →Pulm veins →ends in the LA.

430
Route of Blood Flow through the Heart

Cont…
Anatomy of the heart
Its apex is directed towards the left chest and rests
on the diaphragm, approximately at the level of
the 5th
intercostal space at mid-clavicular line.
The base points toward the right shoulder and lies
beneath the 2nd
rib.

Cont…
The heart wall has three tissue layers:
1. The Endocardium: the membrane which lines the interior
of the heart.
2. The Myocardium: the muscle of the heart; it is the thickest
layer.
3. The Visceral pericardium: which is continuous with the
parietal pericardium.

Cont…
The heart has four hollow chambers of cavities:
1. The right atrium; thin-walled chamber.
2. The right ventricle; the chamber w/c pumps the venous
blood.
3. The left atrium; the chamber w/c receives blood rich in
oxygen.
4. The left ventricle; the chamber w/c has the thickest wall.

Cont….
Four valves of the heart:
1. The Right atrio-ventricular (Tricuspid) valve: right
ventricular contraction leads to closer of this valve.
2. The left atrio-ventricular (Bicuspid/Mitral) valve:
when the left ventricle begins to contract, this valve
become closed.

Cont….
3. The Pulmonic (Semi-lunar) valve: As soon as the
right ventricle has finished emptying itself, the valves
close to prevent blood from returning to the ventricle.
4. The Aortic (Semi-lunar) valve: Following
contraction of the left ventricle, the aortic valve closes
to prevent the flow of blood back from the aorta to the
ventricle.

Cont…
Blood supply to the myocardium
 The muscle of the heart (myocardium) is supplied with
oxygen and nourishment via the right and left coronary
arteries which branch from the base of the aorta.
 Deoxygenated blood drains from the myocardium
through cardiac veins which ultimately empty into the
right atrium.

Cont…
Conduction system of the heart
Two types of controlling systems act to
regulate heart activity:
1. Nerves of the autonomic nervous system that
increase or decrease the heart rate.
2. Intrinsic conduction system (Nodal system).

Cont…
Cardiac cycle
A single CARDIAC CYCLE includes all the
events associated with one heartbeat.
In a normal cardiac cycle, the two atria contract
while the two ventricles relax, then while the two
ventricles contract, the two atria relax.

Cont…
Systole- phase of contraction.
Diastole– phase of relaxation.
At rest each cardiac cycle lasts about 0.8
sec.

Cont….
Cardiac out put
 The volume of blood ejected per minute from the left
ventricle in to the aorta is called Cardiac output.
 It is determined by:
1. The stroke volume (SV) - the amount of blood ejected
by the left ventricle during each beat.
2. The number of heart beats per minute.

Cont…
In a resting adult, SV = 70ml/beat, and heart rate is
about 75 beats/minute.
Thus, CO = SV x HR, HR = Heart rate
= 70ml /beat x 75 beats/min
= 5250 ml/min
= 5.25litters/min.

Cont…
Heart Rates
In a healthy adult person, the heart rate ranges
from 60-100 beats per minute.
However, during rest and sleep, and in sports
men (e.g. Athletes), the heart may beat less
than 60 beats/ minute.

Cont….
Also the heart rate can be faster (i.e.>100
beats/minute) in infants and small children.
1. Heart Rate <60 beats/min = Bradycardia.
2. Heart Rate >100 beats/min =Tachycardia.

HR varies with the following factors
1. Age: higher in newborn infants (120 b/min)
2. Sex: higher in females (85 b/min)
3. Time of the day: ↓morning, ↑evening
4. Resting and sleep: decreased
5. Physical training: low in athletes (45-60 b/min

Cont….
3. Blood Vessels
The blood vessels, together with the four
chambers of the heart, form a closed system
for the flow of blood.
Only if there is an injury to some part of the
wall of this system does any blood escape.

Cont….
Three types of blood vessels:
1. Arteries: Carry blood from the ventricles of the heart out to the
capillaries and the smallest arteries are called arterioles. Arteries carry
blood away from the heart. All arteries carry oxygenated blood except
the pulmonary arteries.
2. Veins: Drain capillaries and return the blood to the heart and the smallest
veins are called venules. veins carry blood toward the heart. All veins
carry deoxygenated blood except the pulmonary veins.
3. Capillaries: Allow gas, nutrients & waste exchanges and it connect the
arterioles and the venules.

Cont….
Structure of blood vessels
Three coats or layers w/c found in arteries and veins:
i. Tunica Externa: It is the outer most layers.
ii. Tunica Media: is the middle layer.
iii.Tunica Interna or Tunica Intima: lines the lumen or
interior of the vessels.

Cont….
Major arteries of the systemic circulation:
Aorta
1.It is the largest of the body.
2.Internal diameter corresponds with the size of
thumb.
3.Decreased only slightly in size as it runs to its
terminus (end).

Cont…..
Aorta Has different parts:
1. Ascending aorta
2. Aortic arch
3. Thoracic aorta
4. Abdominal aorta  descending aorta.

Cont…
Arterial branches of the ascending aorta
 Right and left coronary arteries.
Arterial branches of the Aortic Arch
 Brachiocephalic artery it branches in to Rt common carotid
and Rt subclavian artery.
 Left common carotid artery branches to left internal carotid
and left external carotid.
 Left subclavian artery

Cont….
Arterial branches of the Thoracic Aorta
 Intercostals, bronchial, esophageal, phrenic arteries.
Arterial branches of the abdominal aorta
1. Celiac trunk: left gastric artery, splenic artery and common hepatic
artery.
2. Superior mesenteric artery.
3. Renal arteries.
4. Gonadal, Lumbar, inferior mesenteric artery, common iliac artery.

Cont….
Major vein of the systemic circulation
Many veins are found near the surface of the
body.
Veins draining the head and arms empty in to
the superior vena cava and those draining the
lower body empty in to the inferior vena cava.

Cont…
 Veins at the elbow are often used for removing blood samples
or for IV injections (cephalic, the basilic and the median
cubital veins).
Circulatory routes or circuits
 All the blood vessels together may be subdivided in to two
groups or circuits these are the pulmonary and systemic
circuits.

Cont…
Blood pressure
Blood pressure is the pressure that blood exerts against
the inner walls of the blood vessels.
It is a force that keeps blood circulating continuously.
A clinical condition of elevate or high BP is called
hypertension & the low BP is called hypotension.

Cont…
The difference between systolic and diastolic
blood pressure is called pulse pressure.
Pulse pressure provides information about the
conditions of the cardiovascular system.
For example, atherosclerosis and patent (opened)
ductus arteriosus greatly increase pulse pressure.

• Sites- usual areas used for IV infusion are
The basalic vein- on the inner surface of forarm
Median cubital vein-used for vein puncture
(taking blood)
Cephalic vein--superficial vein of the upper limp
Palmar digital veins-on the top of palm
Dorsal digital veins-on the top of foot
Scalp veins- on the top of head
jugular vein-locate on the neck
• N.B. Techniques of surgical asepsis must be strictly followed for
parental route of drug administration

Cont…
4. Lymphatic system
 It communicates with the blood circulatory system and is
closely associated worth it.
It consists:
1. Lymphatic capillaries
2. Lymphatic vessels
3. Lymphatic ducts
4. Lymph node

Cont….
Large sized materials or substances which are
the result of phagocytosis of pathogenic
micro-organisms are also drained away by in
lymphatic capillaries and vessels.
Lymphoid Tissues are distributed throughout
the body.

Cont…
Lymphoid tissues:
a.Lymph nodes - that help for filtration of lymph.
b.Tonsils - that help for filtration of tissue fluids.
c.Thymus - for processing of T – Lymphocytes.
d.Spleen - that helps for filtration of blood and
destruction of old RBC.

Chapter Eight: Respiratory system
Introduction
The cardiovascular and respiratory systems
cooperate to supply o2 and eliminate co2.
The respiratory system provides for gas exchange
and the cardiovascular system transports blood
containing the gases.

Cont….
Two major Parts of respiratory system:
Upper respiratory tract: Composed of the nose,
the pharynx, the larynx and the trachea.
 Lower respiratory tract: Composed of the
lungs, and all segments of the bronchial tree
(including the alveoli).

Cont….
Upper respiratory system: contains the organs of
respiratory tract that are located outside the chest
cavity.
1. Nasal cavity: Inside the nose, the sticky mucous
membrane lining the nasal cavity traps dust particles,
and tiny hairs called cilia help move them to the nose
to be sneezed or blown out.

Cont…
2. Sinuses: it is air-filled spaces alongside the nose and it makes
the skull lighter.
3. Pharynx (throat): Both food and air pass through the pharynx
before reaching their appropriate destinations.
4. Larynx (voice box): The larynx is essential to human speech.
5. Trachea (wind pipe): Located just below the larynx, the
trachea is the main airway to the lungs.

Cont….
Lower respiratory tract: contains the organs of
respiratory tract that are located inside the chest cavity.
1. Lungs: They’re responsible for providing oxygen to
capillaries and exhaling carbon dioxide.
2. Alveoli (terminal air sacs): It is responsible for
actual gas exchange.

Cont….
3. Bronchi & their smaller branches: The bronchi branch
from the trachea into each lung and create the network of
intricate passages that supply the lungs with air.
4. Diaphragm: The diaphragm is the main respiratory
muscle that contracts and relaxes to allow air into the
lungs.

Cont…
General functions of Nose, pharynx, larynx,
trachea, and bronchi:
1. Serve as conducting passageways that allow air
to reach the lungs.
1.Purify, humidify, and warm incoming air.

Cont…
Three basic functions of nose:
1.Warming, Moistening and Filtering incoming
air to remove some inhaled particles.
2.Receiving olfactory stimuli (smelling).
3.Providing a resonating chamber for speech
sounds.

Cont…
Pharynx has three portions:
1. The most superior portion- Nasopharynx.
2. The middle portion- Oropharynx.
3. The lowest portion- laryngopharynx.
The auditory tubes which drain the middle ear
open into the nasopharynx.

Cont…
Branches of the bronchial tree:
Trachea

Primary bronchi

Secondary bronchi

Tertiary bronchi

Bronchioles

Terminal bronchioles

Cont…
Lungs
 The narrow superior portion of the lungs is called the
apex.
 The broad lung area resting on the diaphragm is the base.
 Each lung is divided into lobes:
o The left lung has two lobes.
o The right lung has three lobes.

Cont…
The narrow space between the parietal and
visceral pleurae is called the pleurae space.
The hilus is an area on the medial side through
which bronchi, pulmonary blood vessels,
lymphatic vessels, and nerves enter and exit.

Cont…
Respiration
It is the process of gas exchange in the body and it
has three basic steps:
1. Pulmonary ventilation or breathing: It is the
inhalation and exhalation of air and involves the
exchange of gas between the alveoli of the lung and
atmosphere.

Cont…
2. External (pulmonary) respiration: Gas exchange
between alveoli of the lungs and the blood in
pulmonary capillaries.
3. Internal (tissue) respiration: Gas exchange
between blood of systemic capillaries and tissue
cells.

Cont…
Mechanisms of breathing or pulmonary ventilation
 Air moves into the lungs when the air pressure inside
the lungs is less than the air pressure in the atmosphere.
 Air moves out of the lungs when the air pressure inside
the lungs is greater than the air pressure in the
atmosphere.

Cont….
LUNG VOLUMES AND CAPACITIES
At rest, a healthy adult averagely breath 12
times per minute.
With each inhalation and exhalation moving
about 500ml of air into and out of the lungs.

Cont…
1. Tidal volume (TV):- It is the volume of one breath which
is 500 ml for a healthy adult at rest.
2. Minute ventilation (MV):- is the total volume of air
inhaled and exhaled each minute. It is the result of
respiratory rate multiplied by tidal volume.
E.g. For a healthy adult at rest: MV = 12 breaths/minute x
500 ml/breath = 6000 ml/min =6L/min.

Cont…
In an average adult, about 70% of the tidal volume
(350 ml) actually reaches the respiratory portion of
the respiratory system and participates in respiration.
The rest 30 %( 150ml) remains in the conducting
airways of the nasal cavity, pharynx, larynx, trachea,
bronchioles and terminal bronchioles.

Cont…
3. The alveolar ventilation rate: is the volume of
air per minute that actually reaches the
respiratory zone.
Example: Alveolar ventilation rate would be
350ml/breath X 12breath/minute = 4200ml/min.

Cont…..
4. Inspiratory reserve volume(IRV):when taking
a deep breath, the person may inhale more than
500 ml air.
The additional inhaled air is called IRV.
 It is 3100 ml for average adult male and
1900ml in average adult female.

Cont….
5. Expiratory reserve volume (ERV):If the person
inhale normally and exhale as forcibly as possible,
the person may exhale more than 500 ml air.
The average adult male (1200 ml) and female
(700ml) push out of air in addition to the 500 ml
of tidal volume.
This extra volume is called ERV.

Cont….
6.Residual volume (RV): Even after ERV is
expelled, considerable air remains in the lungs
and airways.
This is called RV. It is =1200 ml.

QUIZE
1 Write conducting zone of respiration?
2 Where does gas exchange take place ?
3 List the three portion of pharynx?
4 What does mean alveolar ventilation rate and
residual volume?
5 What is Respiration?

Chapter Nine: Digestive system
Introduction
The digestive system is the system that takes in
food and,
 breaks it down into nutrient molecules
 absorbs them into the blood stream,
 and then rids the body of the indigestible
remains.

Cont…
• The digestive system performs 6 basic processes:
– Ingestion: taking in food
– Secretion: water, acid, buffers and enzymes
– Mixing and propulsion: mix food and secretions and move
materials
– Digestion: break down food into nutrient molecules
– Absorption: entrance of the nutrient molecules into the
bloodstream
– Defecation: removal of indigestible remains

Division of the digestive system
• Two groups of organs
– alimentary canal or gastrointestinal (GI) tract
– accessory digestive organs
• The alimentary canal is the continuous muscular tube that
extends from mouth to anus through the ventral body cavity
– Is about 9 m
– Food pass through it and broken down
– It is inside the body but separates its contents from the rest of the
body allowing the food we eat to be processed before being absorbed
and used by the body.
– Provide space for digestion and absorption
• The accessory organs are related to GIT
– produce saliva, bile and digestive enzymes that contribute to the
breakdown of foodstuffs

Organs of the (GI) alimentary canal
•GI is a continuous, coiled, hollow, muscular tube that winds
through the ventral body cavity.
•Its organ Includes:
Mouth
Pharynx
Oesophagus
Stomach
Small intestine, and
Large intestine [which leads to the terminal opening—
anus]

Mouth
• it is a canal through which food enters the
digestive tract.
•also called oral(buccal) cavity.
• It is a mucous membrane lined cavity.
• The lips (labia) lie on its anterior opening
•The cheeks form its lateral walls.
•The hard palate forms its anterior roof, and
• The soft palate forms its posterior roof palate

The pharynx
• Food passes from the mouth to pharynx
• The walls of the pharynx contain two
skeletal muscle layers.
• The circular muscle is divided into
superior, middle, & inferior pharyngeal
constriction, which force food dawn ward
during swallowing.

The Oesophagus(Gullet)
• begins at the level of the cricoid cartilage
• runs from the pharynx through the
diaphragm to the stomach
• It is located posterior to the trachea

cont
• The walls of the alimentary canal organs
from the oesophagus to the large intestine
are made up of the same four basic layers:
1. The mucousa
2. The submucousa
3. The mascularis externa
4. The Serosa

Cont…
1.The mucousa
• inner most layer,
• a moist membrane that lines the cavity or lumen
of cavity or organ.
2.The submucousa
• found just beneath the mucousa.
• It is a soft connective tissue layer containing
blood vessels, nerve endings, lymph nodules and
lymphatic vessels.

Cont..
3.The mascularis externa
• It is a smooth muscle layer. It is made up of
an inner circular layer an outer longitudinal
layer of smooth muscle.
4. The Serosa
 it is the outer most layers. It consists of a
single layer of flat serous fluid producing
cells, the visceral peritoneum.

The Stomach
J-shaped organ in the upper left region of the abdominal
cavity.
•It has different regions:
1. The cardiac region—surrounds the cardioesophageal
sphincter through which food enters the stomach from
the oesophagus.
2. The fundus—the expanded part of the stomach lateral
to the fundus.
3. The body—the midportion.
4. The pylorus—the funnel shaped terminal part of the
stomach.

Cont..
• When it is full, it can hold up to 4 litres of
food.
• The stomach receives parasympathetic
nerve fibbers from the vagus nerve
&sympathetic fibers from the celiac
ganglia.
• It is supplied with blood by branch of the
celiac trunk

The Small Intestine
• It is a convoluted tube extending from the
pyloric sphincter to the ileo-caecal valve.
• It is the longest section of the alimentary tube,
with an average length of 2m (6 feet) in a
living person.
• Have three subdivisions:
• 1.The doudenum
• 2.Jejunum
• 3.and ileum

Cont..
1.The doudenum
 it is in the form of letter C
The first part of the small intestine which
curves around the head of the pancreas.
Is about 25 cm long.
• 2.Jejunum:
The part which extends from the
duodenum to the ileum.
Is about 2.5 m long

Cont…
3.The ileum
Is the terminal part of the small intestine
It joins the large intestine at the ileo-
caecal valve.
Is about 3.6 m long

The Large Intestine
• Begins at the ileo-caecal valve, and extends to the
anus.
• The large intestine has the following subdivisions:
Caecum, Ascending colon, Transverse
colon ,Descending colon, Rectum and Anal Canal

Cont..
1.caecum.
It starts at the duodenojejunal flexure on the left
side of the 2nd
lumbar body.
Sac-like first part of the large intestine.
Hanging from the caecum is the worm-like
appendix.
2.Ascending colon
The second portion that extends upward
along the right side of the abdomen toward
the liver.

Cont..
3.Transverse colon
The ascending colon makes a turn at the right
colic or hepatic flexure, and travels across the
abdominal cavity as the transverse colon.
4.Descending colon
The transverse colon bends at the left colic or
splenic flexure and continues down the left
side of the abdomen as the descending colon.

Cont..
5.Sigmoid colon
As the descending colon enters the pelvis,
it becomes S-shaped and continues as the
sigmoid colon.
• 6. Rectum
The sigmoid colon empties into the
rectum.
7.Anal Canal -A narrow portion of the distal
large intestine.

The accessory digestive organs
• The accessory digestive organs includes: teeth,
Salivary Glands, Liver,Gall Bladder,& Pancreas.
•Teeth:
•consists of two major regions--the crown and the
root.
•The enamel-covered crown is the exposed part of
the tooth
•Enamel is the hardest substance in the body
 Root is the portion of the tooth embedded in the
jaw-bone.

Cont..
•Teeth are classified according to shape and
function as:
1.Incisors-- [chisel-shaped adapted for
cutting]
2.Canine-- [fang like adapted for tearing and
piercing]
3.Premolars-- [bicuspid]
4.Molars-- [have broad crown with rounded
cusps]

Cont..
Premolars and molars are best suited for
grinding.
• A child between 2 and 6 years of age has 20
teeth, called deciduous/ baby/milk teeth.
• These milk teeth will begin to erupt at 6 months
of age, and a baby will have a full set (20 teeth)
by the age of two years.
•Between the age of 6 and 12 years the milk teeth
will be replaced by permanent teeth. A full set of
permanent teeth consists of 32 teeth.

Salivary glands
•Salivary glands produce saliva.
•Saliva is a mixture of mucus and serous fluid.
•The mucus moistens and helps to bind together
into a mass called a bolus, which makes chewing
and swallowing easier.
• salivary amylase begins the process of starch
digestion in the mouth.

The liver
• is the largest gland in the body
It overlies and almost completely covers the
stomach.
It is supplied with blood through two vessels:
•1. The hepatic artery which carries oxygenated
blood, and
•2. The portal vein which carries blood that is rich
in the end products of digest.

The gall bladder
Is a small, thin-walled green sac on the inferior surface of
the liver.
It serves to store bile
When fatty food enters the duodenum, a hormonal
stimulus prompts the gall bladder to contract, squeezing
bile through the cystic duct and into the common bile
duct leading to the duodenum.

The pancreas
• Is a soft, pink, triangular gland that extends
across the abdomen from the spleen to the
duodenum
• produces enzymes that digest fats, proteins,
carbohydrates, and nucleic acids.
• also functions as an endocrine gland producing
the hormones insulin and glucagon.

Digestion and Absorption
•The major functions of the digestive tract are usually summarized in
two words:
digestion and absorption.
I. Digestion:
consists of physical and chemical changes that prepare food for
absorption
• It is of two types: mechanical and chemical digestion.
1.Mechanical digestion:
 Mixing of food in the mouth by the tongue, churning of food in
the stomach, and segmentation in the small intestine are all
examples of physical process contributing to mechanical
digestion.

Chemical digestion
• breaks down large, non absorbable food
molecules to molecules that are able to pass
through the intestinal mucousa into blood and
lymph.
• Chemical digestion consists of numerous
chemical reactions catalyzed by enzymes in
saliva, gastric juice, pancreatic juice and
intestinal juice

I.Absorption
 Is a process by which digested end products of
food are transported from the inside of the
intestines into the circulating fluids of the body.
 Besides digestion and absorption, there are also
other essential activities that the GI tract
performs these includes:
 Ingestion,
 Propulsion,
 and Defecation.

Cont..
I. Ingestion: is the process of taking foods in.
• Propulsion: is the process by which food is
propelled from one organ to the next.
• Defecation:
 Is the elimination of indigestible substances
from the body via the anus in the form of
faeces.

unit ten: URINARY SYSTEM
Introduction to the Urinary System
• The urinary system is a regulatory system
which maintains the purity and constancy of
internal fluids.
• It bears the major responsibility for the
elimination of nitrogenous wastes, toxins, and
drugs from the body.

Functions of the Urinary System
• Filtration of the blood
– Occurs in the glomerulus of the kidney nephron
– Contributes to homeostasis by removing toxins or waste
• Reabsorption of vital nutrients, ions and water
– Occurs in most parts of the kidney nephron
– Contributes to homeostasis by conserving important materials
• Secretion of excess materials
– Assists filtration in removing material from the blood
– Contributes to homeostasis by preventing a build-up of certain materials in
the body such as drugs, waste, etc.
• Activation of Vitamin D
– Vitamin D made in the skin is converted to Vitamin D3 by the kidney
– Active Vitamin D (D3) assists homeostasis by increasing calcium absorption
from the digestive tract

Functions of the Urinary System
• Release of Erythropoietin by the kidney
– Erythropoietin stimulates new RBC production
• Release of Renin by the kidney
– Renin stimulates the formation of a powerful vasoconstrictor
called Angiotensin II
• Release of Prostaglandins
– Prostaglandins dilate kidney blood vessels
– Dilated blood vessels contribute to homeostasis by
maintaining blood flow in the kidneys
• Secretion of H+
and reabsorption of HCO3_
– Eliminates excess hydrogen ions and conserves buffer
material such as bicarbonate
– Contributes to homeostasis by controlling acid/base
conditions in body fluids

Cont..
•The urinary system consists of:
Two kidneys
Two ureters
One urinary bladder
One urethra
•The scientific study of the anatomy, physiology, and
pathology of the kidneys is called nephrology.
• The branch of medicine that deals with the male and the
female urinary system and the male reproductive system
is urology.

The Kidneys
• The kidneys are reddish brown with kidney
bean shape.
• Because it is crowded by the liver, the right
kidney is positioned slightly lower than the left
kidney.
•An adult kidney is about:
12 cm (5 inches) long
6 cm (2.5 inches) wide, and
3 cm (1 inch) thick

Kidney
Location
• Each kidney lies in
paravertebral grooves on
posterior abdominal wall
retroperitoneally
• The kidneys extend from
the level of the T12 to L3
• They receive some
protection from ribs

Kidney: Location
• The right lies
somewhat lower
than left as it is
positioned under
liver

External Anatomy
• The adult kidney weighs about 150 g
• Size: 12 cm long, 6 cm wide, 3 cm thick
• Color: reddish-brown
• Shape: bean-shaped
• The lateral surface of each kidney is convex, while
the medial is concave

Internal Anatomy
• The kidney has three distinct regions
– Cortex
– Medulla
– Pelvis

Ureters
• Thick walled muscular duct with narrow
lumina
• Carry urine from kidneys to urinary bladder
• It measures 25cm (10 in.)

The urinary bladder
• It is a smooth, collapsible muscular sac that
stores urine temporarily.
• The bladder wall contains three layers of
smooth muscle, collectively referred to as the
detrusor muscle
•Although urine is formed continuously by the
kidneys, it is usually stored in the bladder until
its release is convenient.

Urethra
•carries urine by peristalsis from the bladder to
the outside of the body.
•The length and relative function of the urethra
differ in two sexes.
In females it is about 3 to 4 cm long
In males, the urethra is approximately 20 cm
long, and has three regions:prostatic,
membranous and spongy ( penile) urethra.

Cont..
• prostatic urethra begin at the urinary bladder
and passes for about 2.5cm through the prostate
gland.
• Membranous urethra is a short portion where
the urethra passes through the muscular floor of
the pelvic cavity.
• spongy (or penile) urethra is the largest pass
through the penis to the external urethral orifice.

Cont..
• The urethra of the male has a double function:
1.it carries urine out of the body, and
2.it provides the passageway through which
sperm is ejected from the body.
Thus, in males, the urethra is part of both the
urinary and reproductive systems

Terminologies….
• Micturation (voiding): is the act of emptying the bladder
• Urinary incontinence:it is inability to control the external
sphincter voluntarily
 Urinary retention: it is a condition in which the bladder
is unable to expel its contained urine.
 Oliguria is an abnormally low urinary output [100 to 400
ml per day].
 Anuria is a urinary output of less than 100ml per day.

Quiz
1.What is nephron?
2.It is temporary storage place for urine ?
3.What is oliguria?
4.Write the two function of urethra in male?
5.Write the functions of urinary system?
Bonus
Write the process of urination(urine formation)?

UNIT ELEVEN
REPRODUCTIVE SYSTEM
Introduction to the Reproduction System
The reproductive system becomes functionally active since
puberty.
The primary sex organs, or gonads, are the testes in males and the
ovaries in females.
The gonads produce sex cells, or gametes, and secrete sex
hormones.
 The remaining reproductive system structures are accessory
reproductive organs.

External female genitalia
External female genitalia/vulva/:
 Collectively, the external female reproductive organs are called the
Vulva.
External female genitalia(structure) includes:
 Mons Pubis.
 Labia Majora & Minora.
 Clitoris.
 Vestibule.
 Perineum
 Are all visible on external examination.

A. Mons Pubis: it is the pad of subcutaneous fatty
tissue in front of the pubis.
- It is covered by the pubic hair in inverted triangle
fashion.
B. Labia majora: it is the elevation skin and
subcutaneous tissue. Which forms the lateral
boundaries of vulva. The labia majora contains
sebaceous glands, sweat glands and hair follicles.
The labia majora are homologous with the scrotum in
the male. extended from the mons pubis up to perineum.

C. Labia minora:These are two thick skin folds,
devoid of fat, lying on either side with in the labia
majora.
- Posteriorly each labia minora fuse to form a fold
of skin called fourchette.
-Labia minora do not contain hair follicle. It is
homologous with the ventral aspect of the penis.
D. Clitoris: This is a small cylindrical erectile body
situated in the most anterior part of the vulva. It is
analogous to the penis in male. It’s rich vascular,
highly sensitive to temperature, touch, and pressure
sensation.

E. Vestibule: it is a triangular space bounded anteriorly by
the clitoris, posteriorly by the fourchette and on either side by
minora. contains the external urethral meatus, vaginal introitus, and
Bartholins glands.
There are four openings into the vestibule:
I.Urethral opening: situated in the midline just anterior to the
vaginal orifice.
II. Vaginal orifice: Located posterior to the urethral opening.
In virgins and nulliparous the opening is closed by the labia
minora but in parous, it may be exposed. The orifice is
incompletely closed by a septum of mucus membrane called
hymen.

III. Two Bartholin’s duct opening (one on each
side):
It secretes abundant alkaline mucus, during sexual excitement which
helps in lubrication. Each gland has got a duct which opens just
anterior to the Hymen.
F. Perineum (Perineal body): is a pyramidal shaped
tissue .where the pelvic floor and the perineal muscles and fascia
meet. It
is located between the vagina and the anal canal.
-Is the most posterior part of the external femal reproductive
organs.It extends from fourchette anteriorly to the anus posteriorly
and is composed of fibrous and muscular tissue that support pelvic
structures.

Internal female reproductive organs
The internal genital organs in female include :
• Vagina
• Uterus
• Fallopian tubes
• Ovaries
 These require special instruments for inspection.
A. Vagina: The vagina is a muscular passage, 8-10 cm in
length. Locates b/n the cervix and the external genitalia.
Lying b/n the bladder anteriorly & the rectum posteriorly. The
secretions that lubricate the vagina come from glands in the
cervix.
-It is very small but sufficient to make the surface moist.

The vagina has four walls:
 Anterior
 posterior
 and two lateral walls.
The length of the anterior wall measures 7 centimeters and the
posterior wall is about 9 centimeters.
 The vaginal lining has multiple folds & muscle layer. These folds
allow the vagina to stretch considerably during childbirth.
 The reaction of the vagina is acidic, the pH is 4.5 that protects the
vagina against infection.

Functions of the vagina
It serves as:
 Excretory channel for menstrual blood and uterine secretions
 Organ for sexual intercourse and
 passage for the fetus during birth.
B. Uterus: This is a hollow& muscular organ. Situated b/n
bladder & rectum which a fertilized ovum embeds and develops
into a fetus.
Its major function: is protecting and nourishing the fetus until
birth monthly cycle of change, contractions to expel menses
and fetus. During pregnancy, the muscular walls of the uterus
become thicker & stretch in response to increasing fetal size
during the pregnancy.

It has three parts:
I. Body or corpus: The part b/n the isthmus & the opening of
the fallopian tubes. The part that is above the opening of the fallopian
tubes is called the fundus.
II. Isthmus: a constricted part situated between the body and the
cervix.
III. Cervix: The lower most part of the uterus which is
cylindrical in shape. It has two openings the internal os(opening) and
the external os with cervical canal in between.

Three layers of Uterus
A. Perimetrium : The outermost thin membrane layer covering
the uterus.
B. Myometrium :consists of thick muscular middle layer
C. Endometrium: The mucus lining of the endometrial cavity.
Inner most layer of the uterus .It becomes thick during the menstrual
cycle. This is the tissue that builds up each month in awoman of
reproductive age, under the influence of the female reproductive
hormones.

C. Fallopian Tube: paired structures w/c are attached to the
lateral angle of uterine cavity.
It has four parts: 1.Interstitial (part inside the uterine wall)
2.The isthmus (the straight part)
3. Ampulla (typical site of fertilization)
4.The infundibulum.
D. Ovary : Are paired sex glands or organs; each is attached to
the
uterus by the utero-ovarian ligament. These paired female
reproductive organs produce the eggs(ova).
fig 2 .Fallopian tube

Fig 3.Internal female reproductive
organs

Anatomy of the female pelvic
• The pelvis is a hard ring of bone which supports and protects the
pelvic organs and the contents of the abdominal cavity. It is
structurally adapted for child bearing and delivery.
Bony Pelvis Is Composed of 4 bones:
I. Two Innominate( hip) bones. hip bone is composed of three bones:
Ilium
Ischium
Pubis
II. Sacrum
III. Coccyx
The ilium: major portion of the pelvis is composed of two bones,
each called the ilium.It is the flared out part.The greater part of its
inner aspect is smooth and concave,forming the iliac fossa. The upper border of
the ilium is called iliac crest.

Infront of the iliac crest, the bony protuberance called the anterior
superior iliac spine.
Ischium: is the thick lower part of the pelvis formed from two fused
bones; one on either side. It has a large prominence known as the
ischial tuberosity on w/c the body rests while sitting. Ischial spine
used to estimate the station and presenting part
Pubic bones and the symphysis pubis:
 Are bones on either sides and form the front part of the pelvis.
 The two pubic bones meet in the middle at the Symphysis pubic.
 The symphysis pubic is immediately below the hair covered pubic
area. It is landmark to measure the height of the uterus from the
symphysis pubic to funds.

Sacrum: Is a wedge shaped bone at the back of the pelvis
consisting of five vertebrae( small bones that make up the spinal
column or backbone).
- The bottom of the sacrum is a tail-like bony projection called the
coccyx.The anterior surface of the sacrum is concave.The upper
border of the first sacral vertebra known as the sacral promontory.
An important landmark for labor and delivery.

The pelvic canal
• The circular space enclosed by the pubic bones at the
front, and the ischium on either side at the back, is called
the pelvic canal (the bony passage through which the baby must
pass).
• The size and shape of the pelvis is important for labour and delivery.
Classification of pelvic canal:
pelvic inlet
Mid pelvis
pelvic outlet
Pelvic inlet : is formed by the pelvic brim .The pelvic brim is
rounded, except where the sacral promontory and the ischial
spines project into it.

The dimensions in centimeters (cm) of the pelvic inlet
are shown in Figure below in both directions (top to
bottom; and transverse or side to side).
– Transverse diameter: largest (13 cm)
• A.P diameter 12cm
Fig .pelvic inlet

• Midpelvis
Limiting diameter is the interspinous diameter
Normally: > 10 cm
The pelvic outlet: is formed by the lower border of the pubic
bones at the front, and the lower border of the sacrum at the back .
Anteroposterior diameter:
coccyx to symphysis pubis≈13 cm
Transverse diameter:
inter-tuberose (ischial) ≈ 10 cm

Important land marks of female
pelvis
A. Pelvic brim
 Sacral promontory posteriorly
 Upper inner boarder of the body of the pubic bone
 Upper inner boarder of the symphysis pubis anteriorly
B. Mid pelvis
 Ischial spine
C. Out let
 Ischial tuberosity laterally
 Inferior border of symphysis pubis anteriorly.
 Tip of coccyx

Types of female pelvic
There are four types of female pelvises.
1.Gynecoid pelvis:
– Classic female shape
– Has round brim (inlet)
– Diverging mid pelvic sidewalls,
– Far-spaced ischial spines & the ischia spine is blunt.
2. Android pelvis:
– Male in pattern
– Heart-shaped inlet
– Prominent sacral promontory
– Prominent ischial spines
– Shallow sacrum
– Converging mid pelvic sidewalls

3. Anthropoid pelvis:
– Exaggerated oval shape to the inlet & the ischial spine is blunt.
– Largest diameter being antero posterior.
– Limited anterior capacity to the pelvis.
– More often associated with occiput posterior position.
4. Platypelloid pelvis:
kidney shape brim, the ischial spine is blunt.
– Broad, and flat pelvis.
– Largest diameter being transverse diameter.
– Theoretically predisposing to transverse arrest.
 The gynacoid pelvic is an ideal pelvic of the females that is
appropriate to give birth with.

Types of pelvic, the lines at the right shows the greatest diameter of the
pelvic.

The female breasts
 Also known as the mammary glands. Are accessory organs of
reproduction. Situated on each side of the sternum & extends b/n
the levels of the second and sixth rib. The breasts lie in the
superficial fascia of the chest wall over the pectoralis major
muscle, and are stabilized by suspensory ligaments. The shape the
breast is a hemispherical swelling and has a tail of tissue extending
towards the axilla (the axillary tail of spence).Its size varies with each
individual and with the stage of development as well as with age.
breast increases in weghit and size during pregnancy.

• Alveoli: are the milk- secreting cells. Each alveolus is lined by
milk-secreting cells. Small ducts which connect the alveoli are the
Lactiferous tubules. These tubules run to central duct called the
Lactiferous duct. The widened-out portion of the duct where milk is
stored is ampullae lies under the areola.

The menstrual cycle
What is menstrual cycle???
 Also termed a female reproductive cycle. Defined as periodic
uterine bleeding in response to cyclic hormonal changes, that occur
on
the ovary, uterus, and cervix in response to hormonal change.
 Menarche(the first menstrual period)occurs at the average age of
13
years. This may occur as early as age 9 or as late as age 17 years.The
purpose of a menstrual cycle is to bring an ovum to maturity and
renew a uterine tissue bed that will be responsive to its growth should
it be fertilized.

Normal menstrual cycle
Comes every 21-35days(average length is 28 days)
Stays for 3-7days (average length is 5 days)
Amount is 20-80ml
It doesn’t clot
Some women have symptoms of :
 Anxiety
 fatigue
 abdominal bloating
 headache, appetite disturbance
 irritability and depression in pre-menstrual period.

Phases of menstrual cycle
A. Proliferative phase:
 Immediately following a menstrual flow (occurring the first 4 or 5
days of a cycle),
 The endometrium begins to proliferate, or grow very rapidly;
increasing in thickness approximately eight fold.
 This increase continues for the first half of the menstrual cycle
(from approximately day 5 to day 14). This half of a menstrual cycle
is termed as the proliferative, estrogenic (follicular) phase.

B. Secretory phase:
 occurs in the next half of the menstrual cycle. Depends on whether
the released ovum meets the spermatozoa and is fertilized by or not.
 If fertilization does not occur, the corpus luteum in the ovary
begins to regress after 8 to 10 days.
 The production of progesterone and estrogen decreases.
 The withdrawal of progesterone stimulation, degenerate the
endometrium of the uterus (at approximately day 24 or day 25 of the
cycle).
 The capillaries rupture, with minute hemorrhage, the endometrium
sloughs off, and menstruation starts.

Structures of the Male Reproductive system
• The testes ( or male gonads) are the primary reproductive
organs of the male .
• testes have both an exocrine (sperm- producing ) function and
an endocrine ( testosterone-producing ) function.
• Ducts or glands are accessory reproductive structures
that aid in the delivery of sperm to the body exterior.

Testis
• 4cm long, 2.5cm wide.
• Each testis has a large number of lobules.
• Each lobule contains one to four tightly coiled Seminiferous
Tubules that produce sperm by a process called spermatogenesis.
Testis produce sperm .
The rising blood level of testosterone in the young male:
– Stimulates reproductive organs to develop to their adult size.
– Causes the secondary male sex characteristics to appear.
• .

Cont..
– Secondary sexual characteristics typical of males
include:
• Deepening of voice due to enlargement of the larynx,
• Increased hair growth all over the body , and
particularly in the axillary and pubic regions and the
face ( the board).
• Enlargement of skeletal muscles.
• Increased heaviness of the skeleton due to thickening
of the bones .

Epididymis
• Highly coiled tube about 6m long .
• It caps the superior part of the testis and then runs down
its posterolateral side.
• Is the first part of the male duct system. Epididymis
provides a temporary storage site for the immature
sperm that enter it from the testis.

(Ductus) Vas deferens
Runs up ward from the epididymis through the inguinal
canal in to the pelvic cavity and arches over the superior
aspect of the bladder .
• It is enclosed along with blood vessels and nerves , in a
connective tissue sheath called the spermatic cord.
• It empties in to the ejaculatory duct, which passes
through the prostate gland to merge with the urethra.
FUNCTION
• The ducts (vas ) deferens propels live sperm from their
storage sites in to the urethra

Urethra
• Extends from the base of the urinary bladder to the tip
of the penis.
• Is the terminal part of the male duct system.
• Part of both the urinary & reproductive system.
FUNCTION
The urethra serves as a passageway for sperm & urine.

ACCESSORY GLANDS & SEMEN
• These includes: seminal vesicles , the single prostate
gland , and the bulbourethral glands. These glands
produce the bulk of semen (sperm containing fluid).
• Seminal vesicles:
– Located at the base of the bladder.
– Produce  60% of the fluid volume of semen.
– Produce thick , yellowish secretion rich in sugar ( fructose),
vitamin C, prostaglandins and other substances which nourish
and activate the sperm passing through the tract.
– The duct joins that of the ductus deferens to form the
ejaculatory duct.

Prostate gland
– is a single gland.
– It encircles the upper ( prostatic ) part of the urethra
just below the bladder.
– Its secretion is a milky fluid that plays a role in
activating sperm.
– Has several small ducts to the urethra.
– Is immediately anterior to the rectum, hence its size
&
texture can be palpated ( felt ) by digital ( finger)
examination through the anterior rectal wall.

BULBOURETHRAL GLANDS
– Are tiny, pea sized glands (paired).
– Inferior to the prostate gland.
– Produce thick, clear mucus, which drains in to the
penile urethra.

Semen
– Is a milky white, some what sticky mixture of sperm &
accessory gland secretions.
– The liquid provides a transport medium and nutrients and
contain chemicals that protect the sperm & aid their
movement.
– Semen dilutes sperm & hence enhances its motility.
– During ejaculation 2 to 5 ml of semen is propelled out of
the male duct. There are between 50 & 100 million sperm in
each ml.
– A sperm cell consists of structures highly adapted for
reaching and penetrating a secondary oocyte: a head, a
midpiece & a tail.

EXTERNAL GENITALIA
Include the scrotum & penis
• Scrotum:
• Is a divided sac of skin that hangs out side the
abdominal cavity between the legs and at the root of the
penis.
• The scrotum provides a temperature 30
C lower than
body temperature which is the optimal temperature for the
production of a healthy sperm.

Cont..
Penis
• Consists of
– A root
– A body ( shaft) &Glans Penis.
FUNCTION
• Penis is a passageway for the ejaculation of semen and
excretion of urine.
• It is also the male's organ of copulation

Definition of terms
• Fertilization is the union of the ovum and spermatozoa.
• Pregnancy is a maternal condition of having a developing
fetus in the body. It starts at fertilization
• Zygote is a cell that results from fertilization

Cont.
• Ovulation is the process in a female’s menstrual cycle by which a
mature ovarian follicle raptures and discharges an ovum.
The process requires a maximum of 36hours to complete, and it is
arbitrarily separates in to thee phases
oPreovulatory
oOvulatory and
oPost ovulatory

Fertilization
 Fertilization must occur soon after the release of the ovum.
b/c it usually takes place in the outer third of a fallopian tube
(ampullar portion).
The functional life span of a spermatozoa is about 48hrs (may
be ≥72 hrs ) .Also the life span of an ovum is about 48 hrs.
Therefore, sexual coitus during this time may result in
fertilization (pregnancy). The sperm should swim up the
fallopian tube and fuse the ovum. One spermatozoa is active &
can penetrate the membrane of the egg & fuses its nucleus to the
nucleus of the egg.

Fig .Structure of spermatozoa b, Fertilization

Development of the Fertilized Ovum .
Zygote:
 (46xx or 46xy) is a cell that results from fertilization.
 After fertilization the ova passes through the fallopian tube and
reaches the uterus 3 or 4 days later.
 It divides and redivides forming daughter cells named blastomeres.
 Division takes place and the fertilized ovum divides into two cells,
and then into four, then eight, and sixteen and soon until a cluster of
cells is formed known as the morula.
 It reaches 16 cell stage, it is named morula.

Cont.
• These divisions occur quite slowly about once every 12 hours
When fluid filled cavity appears in the morula a blastocyst is
formed.
The cells of blastocyst are arranged in to two layers
Outer layer called trophoblast
Develops in to the placenta & chorion
Inner layer is called embryoblast
Rise to the fetus, umbilical cord & amnion

On day 4 after fertilization the blastocyst into the uterine cavity.
By day 7, it starts embedding itself into the prepared
endometrium which is now called the decidua. This process is
called implantation. Attachment of fertilized ovum(blastocyst) to
the endometrium& embedding of the decidua. The embryo is
the stage after the inner layer formed two layers.The
embryonic period is a period where major structures are
formed & extends up to the end of 7 wks after
fertilization.conceptus after the embryonic period is called
the fetus.All tissue products of conception (embryo/ fetus,
fetal membranes and placenta) are
called concepts.

Development….
 The cells differentiate into three layers, each of which
will form particular parts of the fetus.
The ectoderm mainly forms the skin and nervous system.
The mesoderm forms bones and muscles and also the
heart and blood vessels, including those which are in
placenta.
The endoderm forms mucous membranes and glands
The three layers together are known as the embryonic
plate.

Fertilization: fusion of ovum and sperm on day one
Morula: solid ball of cells after three days
Blastocyst: hollow ball of cells after five days
Trophoblast: forms early embryo, fetal membranes and placenta after
five to seven days
Embryo: the developing human from fertilization to the eighth week of
pregnancy
Fetus: the developing human from nine weeks of pregnancy to birth at around
40 weeks
Neonate: newborn baby from birth to 28 days old
Infant: baby or young child aged less than one year.

Fig . fertilization and implantation

UNIT TWELVE
FLUID AND ELECTROLYTE BALANCE
Objective:
At the end of these chapter you will be able to:
• Compare the locations of intracellular
fluid (ICF) and extracellular fluid (ECF), and
describe the various fluid compartments of the
body.
• Describe the sources of water and solute gain
and loss, and explain how each is regulated.

Cont..
• Introduction:
• The water and dissolved solutes in each of the body’s
fluid compartments constitute body fluids.
• In adults, body fluid constitutes about 55% - 60% of the
total body mass.
• Body fluid is partitioned into two main
compartments.
– Intracellular fluid (ICF) = 2/3 of the body fluid
– Extracellular fluid (ECF) = 1/3 of the body fluid
• 80% interstitial fluid
• 20% plasma

Cont..
• ECF also includes:
• Lymph in lymphatic tissues
• CSF in the CNS
• Synovial fluid in joints
• Aqueous humor and vitreous humor in the eyes.
• Endolymph and perilymph in the ears
• Pleural, pericardial, and peritoneal fluids

Regulatory Mechanism of Fluid Balance
The body is in fluid balance when the required
amounts of water and solutes are present and
correctly proportioned among the various
compartments.
– Osmosis is the primary means of water movement
between intracellular and interstitial fluids.
– The concentration of solutes (mostly electrolytes) in
each fluid determines the direction of water
movement.

Cont…
–The kidney is the major regulator of the body’s
fluid and electrolyte balance.
–Water constitutes approximately 45% - 75% of
body mass. Infants have the highest percentage
of water (up to = 75% of body mass)
–Main sources of body water:
• Ingested liquids = 1600ml per day
• Ingested foods = 700ml per day
• Metabolic water = 200ml per day
• Total daily water gain = 2500ml

Cont..
– Normally body fluid volume remains constant
because water loss equals water gain.
– Main routs of water loss:
• Kidneys = 1500ml
• Skin = 600ml
• Lungs = 300ml
• GI tract = 100ml
– Drinking, the principal method of regulating body
water gain, is governed by the thirst center in the
hypothalamus.

Regulation of solute and body water loss
• Elimination of excess body water or solutes occurs
mainly via the urine and is controlled in part by
hormones.
• These hormones include:
–Angiotensing II and aldosterone
–Anti diuretic hormone (ADH)

Movement of water between fluid compartments
–Intracellular and interstitial fluids normally
have the same osmotic pressure, so cells
neither shrink nor swell
–An increase in the osmotic pressure of one
compartment draws water from the other
compartment.

Electrolytes in body fluids
• In ECF:
–Most abundant cation  Na+
–Most abundant anion  Cl-
• In ICF
–Most abundant cation  K+
–Most abundant anion  Proteins, HPO4
2-
,SO4
2-
–If excess sodium ion remains in the body, water is
osmotically retained, resulting in abnormal
accumulation of interstitial fluid. This is called
EDEMA.

Fluid & Electrolyte Imbalance
1.Body Fluid Imbalance:
i.) Hypovolemia:- is a clinical condition which results
from loss of fluid from circulation, either directly or
indirectly.
e.g. ▪ Loss of water and electrolytes in diarrhea
• Loss of plasma due to burns
• Hemorrhage
• Third space loss (Internal fluid shift into inflammatory
exudates in the peritoneum, such as in pancreatitis.)

Cont..
• When water loss is greater than water gain,
which often caused due to diarrhea &/or
vomiting, it results in a clinical condition
known as Dehydration
• When there is a marked reduction in oxygen
delivery results from diminished cardiac
output secondary to inadequate vascular
volume, it results in Hypovolemic Shock.

Cont….
ii) Hypervolemia:- is a rare condition which results in
excessive body fluid due to some electrolyte imbalance
like hypernatremia and the like. Its management is
depend on treating the underlining cause.

Body Electrolyte Imbalance
1.Sodium(Na+
):136-148mEq/Lit
• Hyponatremia:- due to decreased intake,
increased loss due to diarrhea & vomiting, use
of diuretics; or excessive H2O intake.
• Hypernatremia:- may occur with DHN, H2O
deprivation or excessive Na+
intake or IV fluids.

Cont…
2. Chloride(Cl-
):95-105mEq/Lit
• Hypochloremia:- due to vomiting,
overhydration, CHF, or use of diuretics
• Hyperchloremia:- due to DHN, excessive Cl-
intake or renal failure

Cont..
3.Calcium(Ca2+
): 4.5-5.5mEq/Lit
• Hypocalcemia:- due to increased Ca2+
loss,
decreased Ca2+
intake, increased levels of
phosphates or parathyroid hormone
deficiency.
Hypercalcemia:- may be due to
hyperparathyroidism, some cancers or excessive
intake of Vit-D.

Cont..
4. Potassium(K+
):3.5-5.0mEq/Lit
Hypokalemia:- due to loss of K+
loss secondary
to vomiting or diarrhea, decreased intake,
kidney disease, or therapy with diuretics
Hyperkalemia:- may be due to excessive k+
intake or renal failure

UNIT- THIRTEEN
ACID – BASE BALANCE
Objectives:
• Compare the roles of buffers, exhalation of carbon
dioxide, and kidney excretion of H in
maintaining the pH of body fluids.
• Define acid–base imbalances, describe their
effects on
the body, and explain how they are treated.

Cont…
• Introduction
In a healthy person, the PH of systemic
arterial blood remains between 7.35 and
7.45
The maintenance of acid – base balance is
of critical importance because body
functions are affected by the most minor
changes in PH.

Cont..
There are three major mechanisms that
control the PH of body fluids:
1.Buffer systems
2.Exhalation of CO2 (respiration)
3.Excretion of H+
in urine

Mechanism of Control of PH of Body Fluids
• Buffers:
• Buffers prevent rapid, drastic changes in PH of body
fluids by converting strong acids into weak ones.
The principal buffer systems of the body are:
1.Protein buffer system
– The most abundant buffer in intracellular fluid and
plasma
– (-COOH) and (-NH2)
– Buffer both acids and bases

Cont..
• 2. Carbonic acid – bicarbonate buffer system
– Based on (HCO3) and H2CO3
– In both intracellular and extra cellular fluid
• 3. Phosphate buffer system
– (H2PO42-) and (HPO42-)
– Mainly in intracellular fluid

Exhalation of CO2 (Respiration
 CO2 +H2O H2CO3 H+
+HCO3
-
 Canonlygetridofcarbonicacid
ExcretionofH+
inurine
 ExcreteH+
andreabsorbsHCO3
-

Acid – base imbalances
• 1. Acidosis
– Arterial blood PH of less than 7.35
– Effect: depression of the CNS.
– If PH is less than 7 depression of CNS is so severe (individual
becomes disoriented, then comatose, and may die.
• 2. Alkalosis
– Arterial blood PH of greater than 7.45
– Effect: over excitability in both CNS & PNS neuron
• (Nervousness, muscle spasms & even convulsion and
death may result)

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