Chapter 25, Problem 1TYR

Summary Introduction

Introduction:

Lipids are hydrophobic in nature, so digestion and absorption of lipid is a more complicated process when compared to protein and carbohydrate digestion. Lingual lipase in the mouth secreted by intrinsic salivary glands digests small quantity of fat. This enzyme moistens the mouth even if we do not eat anything. Emulsification droplets, micelles, and chylomicrons are involved in lipid digestion.

Answer to Problem 1TYR

Correct answer:

Lingual lipase is an enzyme that begins the digestion of fat in the mouth; this is more active in the stomach because of the acidic pH. Therefore, option b is correct.

Explanation of Solution

Justify the reasons for the correct statement:

Lingual lipase is secreted by lingual serous glands that is collected in the stomach between and after every meal.

Option (b) is given as, “lingual lipase”.

Lingual lipase is one of the acidic enzymes involved in the digestion of fat.

Hence, option (b) is correct.

Justify reasons for the incorrect statements:

Option (a) is given as, “chymotrypsin”.

Chymotrypsin is secreted by the pancreas that digest proteins. Hence, it is a wrong answer.

Option (c) is given as, “carboxypeptidase”.

Carboxypeptidases are pancreatic secretions that are involved in protein digestion; it removes amino acid from the –COOH end. Hence, it is a wrong answer.

Option (d) is given as, “enteropeptidase”.

The trypsinogen (pancreatic zymogen) is converted to trypsin by enteropeptidase. Hence, it is a wrong answer.

Option (e) is given as, “dextrinase”.

Dextrinase enzyme in the small intestine is involved in digestion of starch, converting it into glucose. Hence, it is a wrong answer.

Hence, options (a), (c), (d), and (e) are incorrect.

Conclusion

Lingual lipase secreted by lingual serous glands is more active in the stomach.