4. Organ Systems Flashcards
Define what an organ is
different tissues organised into functional units
What is the difference in structure of a herbivores digestive system compared to a carnivore?
a herbivore has a longer ALIMENTARY CANAL than a carnivore.
this is because the function of the digestive system is to process food and vegetation is harder to digest because of the cell walls - cellulose
What are the two types of digestion in the mouth and what happens in these processes?
mechanical digestion - chewing food.
- Increases surface area
- makes food easier to swallow
chemical digestion - saliva
- Protects oesophagus
- moistens food to make it
What are three functions of the stomach?
Storage of food
digestion - enymes and hydrochloric acid kills fungi and pathogens
this is because of the structure of the stomach has high surface area and a low pH (2)
What is chyme?
A mixture of ingested food and digestive juices
What occurs in the first section of the small intestine and what is this part called?
In the duodenum, enzymatic hydrolysis of food macromolecules takes place
What is the function of the pancreas?
- Its an accessory digestive organ
- secretes pancreatic juices containing
water,
salt,
bicarbonate to neutralise chyme,
digestive enzymes the to break down protein
What is the structure of the small intestine and how does this help function?
The small intestine have epithelial cells that have many folds to increase surface area. The function of this is to all for food to be absorbed into the blood
What is the function of the large intestine?
- To recover water - the liver, pancreas and gall bladder release water. Large intestine tops it back up
- breaks down polysaccharides (starch and cellulose)
- elimination of digestive waste
- has bacteria
What is a cecum in humans and what is its function?
Its an appendix in humans and its a store of bacteria to help break down cellulose and starch - therefore well developed in horses, guinea pigs and rabbits (non ruminant herbivores)
What are five important features of a ruminant (cow, sheep, deer) digestives tract?
- Food is chewed, swallowed regurgitated then chewed again
- stomach has four chambers
- bacteria assist in the digestion of cellulose
- tounge is prehensile (capable of grasping)
- saliva has NO amylase (enzyme to turn starch into sugars)
What is the main function of the liver? (2)
To filter and process the nutrient-rich blood passing through it
produces bile for digestion of fats
What are the other five important functions of the liver?
- Metabolism of macromolecules
- proceses drugs and hormones
- removes the waste product bilirubin
- synthesis of bile salts
What is the two components to create the structure of the circulatory system and what is the function?
arteries: pump blood around the body and chemical exchange
veins: return blood from capillaries to the heart
how does the double ciruclation of the heart work?
- right atrium pumps deoxygenated blood to right ventricle
- right ventricle pumps deoxygenated blood to lung capillaries for oxidising thought the pulmonary artery
- pulmonary vein pumps oxygenated blood to the left atrium
- left atrium pumps to left ventricle
- left ventricle pumps to aorta
What does the respiratory system (function) and how does the structure of it support it? (3 structure points)
Respiratory system optakes oxygen and discharges carbon dioxide. The structure of the respiratory surfaces therefore are
- Thin
- havea large surface area
- moist to maintain cell membrane
What are the two region structures of a kidney and what are the functions?
The structures are the outer renal cortex and the inner renal medulla. Kidneys function is to remove waste through the uretha as urine
What is a nephron?
A nephron is the basic functional unit of the vertebrate kidney. Its a tubule which filteres waste and creates urine
What are the two tissues which make up the mammary gland? What is their structure?
parenchyma - the secretory tissue, epithelium lining alveoli
What are the secretory cells around the lumen in the mammary gland? How does their structure relate to function?
alveoli! They have a high surface area which means lots of milk can be held in them. Milk is ejected into small ducts leading to larger ducts then to the teat canal
How is milk production stimulated? Think of the control centre and the type of hormone (4 steps)
- Sensor nerves signal the hypothalums
- oxytocin released by the pituitary
- Travels in blood to myepithelial cells
- contraction causes milk ejection
