All about biology in the 2 bimester biology
- 1. Term 2 INTRODUCTION This article will tell you how the digestive system functions and what is it. You will see many images about the digestive system of animals, there will be many videos and also some games in which you will recognize the parts that composed the digestive system, also cells, and many ways to see xylem. Interactive game http://kidshealth.org/parent/interactive/digestive_it.html What is the digestive system? Is when the organs processes food and convert it in little molecules and separate the minerals, proteins, etc and eliminate the minerals that are not necessary. “Digestive Systems in Different Animals “Different species of animals have different digestive systems which are adapted to their unique requirements. The type of food, method of food gathering and energy needs are some factors that influence the type of digestive system an animal needs in order to survive. Herbivores have a more specialized digestive system than that of a carnivore because it is more difficult to digest vegetation than meat. The teeth are flat so that grass and plant material can be ground down, rather than the sharp teeth of carnivores designed to tear flesh. Animals which eat both plants and meat, such as humans, have both types of teeth so that they can perform both functions. In simple animals the digestive system is not complex; animals require a storage organ, such as the stomach, which allows them usually containing a single tube. As the animal becomes more complex organs with specialized functions develop. Higher order to take in large amounts of food in one feeding and then use its energy over a long period of times. This makes it possible for them to devote time to activities other than feeding.
- 2. Bird Birds need a high body temperature which requires a large amount of energy to maintain. This means that birds need to eat larger amounts of food to gain the energy they need every day to survive. In order to do this they have a specialized digestive system where there is an efficient absorption of energy. Food passes through very quickly and is all absorbed, leaving little waste. Birds have no teeth so digestion does not begin in the mouth, all of the food breakdown must occur within the digestive system. Food enters through the mouth where it passes down the esophagus into the crop. This organ is where the food is stored and begins to soften. From here it moves into the stomach, which is called the proventriculus. This acts as a true stomach where digestive juices continue to chemically break down food. The partially digested food moves into the muscular gizzard, which has a rough lining to break down the food further. It sometimes contains sand or pebbles which have been swallowed by the bird, which add to the grinding process. The food moves into the intestine, first into the small intestine and then onto the large intestine. At the point
- 3. where the small and large intestine meet are two pouches or caeca, which absorb the water from the food. In herbivores this is the site of cellulose deposition. The food becomes harder and enters into a chamber called the cloaca. It then passes out of the body through the cloacal lining. Horse An adult horse, over five years old, has 40-42 teeth which include incisors, canines and cheek teeth. The incisors work together with the lips to grasp and move food around the mouth. The molars are used to grind down food, making it easier to digest. The digestive system has developed to effectively break down and digest fodder, with the stomach being smaller than that of other cud chewing animals. The average adult horse is able to hold 7.5-9.5 litres (2-2.5 gallons) of chyme in their stomach. The small intestine is 18-21 meters (60-70 feet) long, while the large intestine is enormous, adapted to digesting grass and hey. The caecum is a pocket between the large and small intestine and is able to hold 15-65 liters (4-17 gallons) while the large colon can hold 60-150 liters (16-34 gallons). In the large intestine food is broken down through fermentation by both bacteria and protozoa. Food may remain in the intestine for up to 55 hours. Insect The digestive system in insects is basically a tube that begins at the mouth and ends at the rectum. It can be divided into a pharynx, esophagus, stomach, intestine, colon and rectum. The stomach or midgut has glands called the gastric ceca which secrete the digestive juices. The malpighian tubes remove the nitrogen rich waste from the blood. Each tube empties at the connection between the stomach and large intestine, producing an end product of uric acid, which is passed with faces. Insects such as the praying mantis are carnivorous and begin to digest their food by chewing. Other insects such as wasps paralyse their pray and lay their eggs in the bodies. This provides a living food supply for the young, providing their immediate source of food. Termites gain their energy from wood and begin to digest the cellulose before it enters the digestive system. Protozoans are released onto the wood and begin its breakdown, continuing to act on the wood once it is passed onto the stomach. Flatworms have a simple digestive system, with a single tube serving as both mouth and anus. Snake Snakes eat all parts of their pray and need a specialized digestive system to gain the most nutrients from their food. Their teeth are very thin and usually curve backwards. Their function is not to grind down food as it is in most animals; rather it is to capture prey. The food is swallowed whole, thus the teeth perform a specialized function. They have powerful digestive enzymes to break down the hair, feathers, bones, organs and other parts of their food. The salivary glands also produce strong enzymes which are also used to kill the organism. If saliva enters the wounds of the animal it will begin the digestive process and cause severe tissue
- 4. damage, which can often lead to the death of the animal. These toxic substances are found in the saliva of many non poisonous snakes. In poisonous snakes it is the salivary glands which have developed into venom sacks, with the venom being a highly toxic form of saliva. Mollusk The mollusk digestive system has millions of microscopic hair like fibers along the main digestive tract and has several divisions for the different organs. The first section contains the mouth and esophagus and is the site of the initial breakdown of food. There is a specialized file like radual found in the mouth, which acts like teeth or a tongue in the food breakdown. Oysters, clams and muscles do not feature the radula, as they are filter feeders, the food is already filtered when it enters the mouth and continues down the digestive tract. It reaches the liver and stomach, which continues the digestion. In many mollusks the stomach has a flexible rod, which is made up of mucus and proteins in a crystalline structure. This secretes the digestive juices and enzymes and acts as a kind of stirring stick, mixing up the stomach contents to aid digestion. The final section of the digestive tract contains the intestine and anus, from which the waste is removed.” What are the organs that process the digestive system? The mouth: the mouth is used to convert food in little pieces of it Esophagus: is used to transport the little pieces of food to the stomach Stomach: mix the food with gastric juices and melts the food. Duodenum: is when the food is separate into needed thing and other things that are don’t needed and is transport it to the anus Small intestine: the nutrients are taken to the blood. Large intestine: absorb the water and the solids are taken to the anus Anus: is when the solids are eliminated
- 5. On the digestive system the organs function in order that the nutrients that are not needed are expulsed by the anus and the nutrients, mineral, vitamins that are needed, are taken in which they belong to. The digestive system starts with the mouth that mashes the food, after is transported by the esophagus to the stomach on the stomach the food is mixed with HCI (hydrochloric acid) after is transported to the duodenum in there the nutrients are separated with the solids that are not needed then that solids are transported to the small intestine after is taken to the large intestine
- 6. in there the water of the solids are absorbed, later is taken to the anus in there that solids are expulsed. Ways of see the xylem, phloem and stomata and understanding what is Xylem: is the principal water-conducting tissue vascular plants also Xylem caries water and dissolved nutrients from the roots throughout the plant. Phloem: is movement of water through the xylem it also carries distributes the products of photosynthesis (mainly from the leaves) to the rest of the plants. Stomata: Are apertures structure on a plant How to see Xylem, phloem and stomata 1. You have to look for a plant with cute stem 2. Look at the plant and see the stem it have or the leave 3. With a knife or something, cut a little bit of the stem or with the leave take out the vein and cut it 4. In a slide with another slide on top put it on the microscope and in there you will see all xylem, phloem and stomata
- 7. 1. The carbon cycle begins with photosynthesis in plants False Plants are primary consumers of carbon dioxide. True Animals are primary consumers of carbon dioxide. False Humans are producers of carbon dioxide. True Carbon dioxide is easily dissolved in water. True Humans and animals release carbon dioxide into the air during photosynthesis
- 8. False All of the carbon in existence is continually recycled in the carbon cycle True Where does the carbon come from that the plants use? Air Are human’s primary consumers of carbon dioxide or secondary consumers? Neither. Humans produce carbon dioxide How does carbon get into the soil? All of the above 2. Where does photosynthesis take place? in the chloroplast What is the first step in photosynthesis? Trapping sunlight In addition to sunlight, what else is required for photosynthesis to take place? Carbon dioxide and water How many groups of reactions take occur in the process of photosynthesis? Two What are the products of photosynthesis? Sugar and oxygen What are the products of photosynthesis? Respiration What happens to sunlight in photosynthesis? It's converted to chemical energy and stored Which group of reactions is responsible for the photo in photosynthesis? Light reactions
- 9. Which group of reactions is responsible for the synthesis in photosynthesis? Dark reactions 3. Which cell feature is responsible for making proteins? Ribosomes What is the name of the jelly-like substance that is inside the cell? Cytoplasm What cell feature is responsible for powering the cell? Mitochondria Where in the cell does DNA replication take place? Nucleus What is one major feature that plant cells have that animal cells do not? Cell wall What is one major feature that plant cells have that animal cells do not? Lysosomes Which cell feature processes proteins? golgi apparatus Which cell feature transports ribosomes? endoplasmic reticulum The plant cell structure where photosynthesis takes place is called... Chloroplast What cell feature is responsible for storing water? Vacuole Cells are the Starting Point
- 10. All living organisms on Earth are divided in pieces called cells. There are smaller pieces to cells that include proteins andorganell es. There are also larger pieces called tissues andsystems. Cells are small compartments that hold all of the biological equipment necessary to keep an organism alive and successful on Earth. A main purpose of a cell is to organize. Cells hold a variety of pieces and each cell has a different set of functions. It is easier for an organism to grow and survive when cells are present. If you were only made of one cell, you would only be able to grow to a certain size. You don't find single cells that are as large as a cow. Also, if you were only one cell you couldn't have a nervous system, no muscles for movement, and using the internet would be out of the question. The trillions of cells in your body make your life possible.