Flashcards
Animal systems part 2
Cards in this deck (13)
- 1Define absorptionMovement of digested food molecules through the wall of the intestine into the blood
- 2Significance of villi in increasing the internal surface area of the small intestineLarger surface area for absorption, the distance travelled by nutrient molecules are decreased allowing for more efficient absorption of nutrients
- 3What is the small intestineRegion for the absorption of digested food
- 4Structure of a villusone cell thick, amino acids and sugar molecules are absorbed through the thin villus wall into the blood capillary (nutrients absorbed will come together to form the hepatic portal vein that goes directly to the liver for processing), fatty acids and glycerol are absorbed into the lacteal (also a capillary, absorbs fats in the villi).
- 5Role of the liver in the metabolism of glucoseRemoves excess glucose from the blood and stores glucose as glycogen. If the body needs more glucose than what is stored as glycogen, the liver will make more from other molecules (amino acids, fatty acids)
- 6Role of fat as an energy storage substanceWhen we are short of energy our body uses the fat. Fat can release more than twice more energy than carbohydrates or protein.
- 7Define circulatory systemMade up of the blood, heart, blood vessels. Main transport for all mammals. It is a network of tubes, called blood vessels. A pump, the heart, keeps blood flowing through the vessels, valves in the heart and veins prevent backflow of the blood.
- 8Define double circulationBlood passes through the heart twice for each complete circulation of the body, right side – collects deoxygenated blood from the body and pumps it to the lungs (thus, low pressure circulation in the lungs), left side – collects oxygenated blood from the lungs and pumps it to the body (thus, high pressure circulation to the body tissues), double circulatory system helps to maintain blood pressure (makes circulation efficient)
- 9Structure of the heartFour chambers, 2 atria’s (top) & 2 ventricles (bottom). There is a valve between the atrium and ventricle on each side of the heart. The 2 sides of the heart are separated by the septum. The left side has a more muscular wall, as it has to pump blood across the body. 4 major blood vessels associated with the heart: pulmonary veins, aorta, vena cava, pulmonary artery
- 10How is coronary heart disease causedCholesterol, which is made in the liver, may stick to the walls of the coronary arteries, which would narrow and slow down the flow of blood.
- 11Risks of coronary heart diseaseEating a diet with too much saturated fat, being over weight, smoking, taking little or no exercise, stress, genes, age, sex
- 12Avoiding coronary heart diseaseTake regular exercise, do not smoke, take care of your diet – eat more poultry and fish, cut down on fried food, eat less red meat, eat more fresh fruit and vegetables
- 13Functions of the heartPumps blood out when muscles contract. When it relaxes the heart fills up with blood again. When blood is pumped out the valves open, but then it closes to prevent blood flowing back in.