2. Heartburn could be caused by a poorly working a) uvula b) pyloric sphincter c) cardiac sphincter d) epiglottis

Transcription

1 Biology 12 Digestion Practice Test Section 1: Digestion Structures and Functions 1. The exit from the stomach is the a) cardiac sphincter b) epiglottis c) pyloric sphincter d) uvula Name: 2. Heartburn could be caused by a poorly working a) uvula b) pyloric sphincter c) cardiac sphincter d) epiglottis 3. The structure which prevents food going down the airway is the a) uvula b) epiglottis c) cardiac sphincter d) tonsils 4. In the digestive process, where is physical digestion first started? a) mouth b) esophagus c) stomach d) small intestine 5. Where may peristalsis not occur? a) esophagus b) epiglottis c) small intestine d) stomach 6. E. coli bacteria, found in the colon, are useful to humans because they a) lubricate the intestines b) compact fecal matter c) increase the surface area for digestion d) produce vitamins, amino acids and other growth factors 7. Identify the structure labeled X in the diagram. a) Bile duct b) duodenum c) cardiac sphincter d) pyloric sphincter 8. Blockage of the bile duct would most likely a) decrease bile production b) affect the digestion of fats c) raise the ph of the duodenum d) decrease the quantity of feces 9. A major function of the colon is to a) digest fats b) absorb water c) store protein d) secrete hormones

2 10. Which number represents the organ that secretes amylase? a) 2 b) 3 c) 5 d) Digestive secretions from the liver and pancreas empty into the a) colon b) stomach c) duodenum d) esophagus 12. During swallowing, which process does not occur? a) secretion b) digestion c) breathing d) peristalsis 13. The function of saliva is to a) digest fats & proteins b) lubricate food and digest starch c) stop the trachea from drying out d) kill bacteria by acidic medium in mouth 14. Surgical removal of the gall bladder would affect the digestion of a) fats b) proteins c) minerals d) carbohydrates 15. What part of the digestive system secretes hydrochloric acid? a) mouth b) stomach c) colon d) small intestine 16. During swallowing food is prevented from entering the trachea by a) epiglottis b) soft palate c) cartilage rings d) mucus in larynx 17. The function of the stomach is to a) store food and digest proteins b) store nutrients and produce bile c) absorb water and produce vitamins d) absorb water and digest carbohydrates

3 18. A ring of muscle that controls what enters and leaves different parts of the digestive system. a) sphincter b) epiglottis c) appendix d) gall bladder 19. Which structure prevents food entering the nasal cavity? a) epiglottis b) pyloric sphincter c) uvula d) soft palate 20. What is the name of the substance that emulsifies fat? 21. What is the name of the substance which helps to neutralize stomach acid in the duodenum? 22. What structure stores bile in the body until it is needed? 23. Describe the role of the following structures during swallowing a) soft palate b) uvula c) epiglottis 24. Explain 3 functions of the colon (large intestine) (including E. coli bacteria) (3 marks) 25. Explain how the anatomy (structure) of the small intestine allows it to: a) digest food b) absorb nutrients c) carry out peristalsis

4 26. Label the following diagram. Section 2: Enzymes 27. Which of the following enzymes are produced by more than 1 gland in the digestive system? a) pepsin b) trypsin c) lipase d) amylase 28. Trypsin and pepsin both act upon a) fats b) carbohydrates c) proteins d) disaccharides 29. The end product of the action of amylase is a) sucrose b) amino acids c) fatty acids d) maltose 30. Trypsin works in the a) mouth b) stomach c) liver d) duodenum 31. Peptidases work in the a) stomach b) mouth c) esophagus d) small intestine 32. The enzymes of the digestive system act by a) oxidation b) hydrolysis c) dehydration d) reduction

5 33. Which of the following helps in the digestion of lipids? a) bile b) pepsin c) amylase d) HCl 34. Which of the following helps in the digestion of starch? a) bile b) pepsin c) amylase d) HCl 35. Which of the following helps in the digestion of protein? a) bile b) pepsin c) amylase d) lipase 36. Which of the following chemical conditions produces the active enzyme pepsin? a) neutral b) high ph c) acidic d) alkaline 37. Enzymes that work on all classes of foods are secreted by the a) stomach b) pancreas c) small intestine d) liver 38. Which of the digestive enzymes is incorrectly matched to its substrate? a) trypsin-nucleic acid b) pepsin - protein c) lipase - fat d) amylase - starch 39. Which of the following enzymes is correctly matched with its site of production? a) trypsin-salivary glands b) lipase-stomach c) amylase-pancreas d) pepsin- liver 40. Trypsin works best in a) ph 3 b) ph 7 c) ph 8 d) ph Amylase will work in a) ph 3 or 4 b) ph 7 or 8 c) ph 5 or 6 d) ph 4 or 5

6 42. After chewing a starchy food for a few minutes, a person experiences a sweet taste in the mouth. Which of the following enzyme-substrate complexes was involved? a) amylase-carbohydrate (polysaccharide) b) trypsin-peptide c) lipase-triglyceride d) maltase-glucose 43. What would occur if sodium bicarbonate ions were not present in pancreatic juice? a) bile would not emulsify fat b) trypsin would not break down proteins c) protein digestion in stomach would not occur d) water would not be reabsorbed in colon 44. Which enzyme catalyzes the following reaction? fat fatty acids a) lipase b) pepsin c) maltase d) trypsin 45. Starch digestion begins in the 46. The other place starch digestion occurs is in the 47. Which food type is the only one which is digested in the stomach? 48. Name the group of enzymes which act on peptides in the small intestine? 49. What chemical is needed to change pepsinogen into pepsin? Where does this happen? 50. An experiment was conducted to study the ability of molecules to pass through a membrane selectively permeable to nutrient building blocks. Steps: 1. Three (3) labeled thistle tubes were prepared with the contents shown in the diagrams below. 2. Each tube was placed into a beaker of distilled water at 37 C for 1 hour. 3. After 1 hour, the H2O in the beaker was tested for the presence of various molecules. Identify the molecules found in each beaker after the end of 1 hour. Give an explanation for your choice. Experiment Explanation

7 51. In an experiment designed to test the effectiveness of two protein digesting enzymes (X and Y) under various conditions, the following procedure was carried out. Identical protein substrates were placed in a series of numbered beakers The temperature and ph of the beakers was varied Similar amount of enzyme (X & Y) were added to the beakers & resulting activity was observed (the contents of the beakers were checked after 2 hours. Table 1: Product levels resulting from the action of enzyme X Table 2: Product levels resulting from the action of enzyme Y a) Identify enzyme X b) Identify enzyme Y c) What is the common product of these enzymatic reactions? d) Where in the body does each enzyme function best? e) How would the amount of product change if a heavy metal such as lead were added to beaker 1 at the start of the experiment? Give an explanation for your answer. f) Which experiment condition appears to be the least suitable for the functioning of both enzymes? Section 3: Absorption of Nutrients 52. Fatty acids and glycerol are first absorbed into the a) blood capillaries of the villi b) blood capillaries of the stomach c) lacteals d) lymph veins 53. Which of the following are absorbed by lacteals? a) starches b) fatty acids c) amino acids d) monosaccharides

8 54. Absorption of digested food products occurs largely in the a) liver b) stomach c) large intestine d) small intestine 55. After products of digestion are absorbed, they travel through the blood stream to the a) pancreas b) liver c) colon d) lungs 56. What is the only category of carbohydrates which can be absorbed by the intestinal villi? 57. When fatty acids pass through the walls of the villi they are first drained away by the 58. Into what substances must all proteins be converted before they can be absorbed into the blood stream? 59. To be absorbed into lacteals, fats must be changed to Section 4: Liver Functions 60. Damage to the liver may impair which function? a) produce bile b) convert glycogen to glucose c) detoxifying blood d) all of the above e) none of the above 61. Describe each of the following functions of the liver. a) Produce bile b) Detoxification of drugs and alcohol c) Homeostasis of blood glucose after a meal d) Homeostasis of blood glucose between meals e) Production of NH 3 (ammonia) and urea

9 Section 5: Pancreas, Insulin, Glucagon and Blood Glucose 62. Where is insulin produced? Where is glucagon produced? 63. Insulin and glucagon are examples of secreted proteins that travel through the blood stream and are classified as? 64. When would insulin be secreted? List 3 functions of insulin. 65. When would glucagon be secreted? List 3 functions of glucagon. 66. What are negative feedback cycles? 67. Give an example of a negative feedback cycle in the homeostasis of blood glucose.