Digestion of Food-2:
1. What is the structural and functional unit of the liver?
A. Hepatic lobules
B. Hepatic cells
C. Hepatic ducts
D. Cystic duct
Answer: A
Explanation: The hepatic lobules are the structural and functional units of the liver containing hepatic cells arranged in the form of cords. Each lobule is covered by a thin connective tissue sheath called as Glisson’s capsule.
2. Which part of the pancreas produces hormones?
A. Endocrine part
B. F cells
C. Exocrine part
D. β cells
Answer: A
3. What per cent of starch is hydrolyzed by salivary amylase?
A. 30 %
B. 70%
C. 80%
D. 95%
Answer: A
Explanation: In the buccal cavity, about 30% of starch is hydrolysed by salivary amylase or carbohydrate splitting enzyme which acts at a pH of 6.8 and converts starch into a disaccharide- maltose.
4. Which of the following types of cells is not present in the stomach?
A. Neck cells
B. Chief cells
C. Parietal cells
D. Paneth cells
Answer: D
Explanation: The mucosa of the stomach has gastric glands. Gastric glands have three major types of cells namely:
i. Neck cells
ii. Peptic or chief cells
iii. Parietal or oxyntic cells.
5. Pepsinogen is activated by which of the following secretions?
A. Trypsin
B. Salivary amylase
C. Hydrochloric acid
D. Rennin
Answer: C
Explanation: The proenzyme pepsinogen on exposure to hydrochloric acid gets converted into the active enzyme pepsin which is the proteolytic enzyme of the stomach. Pepsin converts proteins into proteoses and peptones.
6. For how much time stomach stores food?
A. 2-3 hours
B. 3-4 hours
C. 4-5 hours
D. 6-7 hours
7. 4.5 pH is optimal for the action of pepsin.
A. True
B. False
Answer: B
Explanation: Hydrochloric acid provides the acidic pH 1.8 which is optimal for the action of pepsins. The mucus and bicarbonates present in the gastric juice play an important role in the lubrication and protection of the mucosal epithelium of the stomach.
8. What is the milk digesting enzyme of infants?
A. Lipases
B. Lactose
C. Rennin
D. Pepsin
Answer: C
Explanation: Rennin is a proteolytic enzyme found in the gastric juice of infants which helps in the digestion of milk proteins. Small amounts of lipases are also secreted by gastric glands.
9. Which layer of the alimentary canal generates various types of movements in the small intestine?
A. Mucosa
B. Sub-mucosa
C. Muscularis
D. Serosa
Answer: C
Explanation: Various types of movements are generated by the muscularis layer of the small intestine. These movements help in the thorough mixing up of the food with various secretions in the intestine and thereby facilitate digestion.
10. Which of the following is not the secretion released into the small intestine?
A. Bile
B. Pancreatic juice
C. Salivary amylase
D. Intestinal juice
Answer: C
