Digestion and AbsorptionNEET Zoology · Class 11 · NCERT Chapter 4

Solution

Succus entericus is intestinal juice contains maltase, lipase, nucleosidase. Nucleases are the enzymes of pancreatic juice.

Solution

– Kupffer-cells are phagocytic cells of liver. – Zymogen cells are enzyme producing cells. – Paneth cell secretes lysozyme which acts as anti-bacterial agent. – Argentaffin cells are hormone producing cells.

Solution

Rennin and Pepsin enzymes are present in the gastric juice. Maltase is present in the intestinal juice.

Solution

Option (4) is the correct answer because digestion of polysaccharides like starch occurs in mouth and digestion of disaccharides occurs in small intestine. Option (3) is incorrect because saliva contains mucus which helps in the lubrication of oral cavity. Option ( 1) is incorrect because saliva contains an antibacterial agent -lysozyme so that it controls bacterial population in mouth. Option (2) is incorrect because digestion of complex carbohydrates are performed by secretions from salivary glands.

Solution

- Peptic cells secrete proenzyme pepsinogen.
- Goblet cells secrete mucus.
- Oxyntic cells secrete HCl and intrinsic factor for absorption of vitamin B₁₂.
- Hepatic cells secrete bile juice.

Solution

The ileo-caecal valve prevents the backflow of undigested and unabsorbed substances from the caecum into the ileum. NCERT XII chapter Digestion and Absorption describes this valve as a one-way mechanism, so option (c) is correct.

Solution

The correct answer is option no. (1) as The structure used for griding the food particles – Gizzard The structure used for storing of food – Crop Ring of 6-8 blind tubules at junction of foregut and midgut which assists in secretion of digestive juices – Gastric Caeca Ring of 100 -150 yellow coloured thin filaments at junction of midgut and hindgut which assists in elimination of nitrogenous wastes – Malpighian tubules