Question

Which one of the following enzymes carries on the initial step in the digestion of milk in humans?

• A. Rennin
• B. Pepsin
• C. Lipase
• D. Trypsin

Answer 1

The correct option is B

Pepsin

The correct option is B.

The explanation for the correct option:

1. Digestion of Carbohydrates starts in the mouth whereas digestion of proteins starts in the stomach.
2. Milk contains milk proteins that start to digest in the stomach where various enzymes breakdowns milk proteins.
3. In the stomach, pepsin is present along with gastric juices.
4. In the process of milk digestion, the initial step happens in the acidic environment of the stomach where pepsin breaks down the milk protein into smaller fragments.

The explanation for the incorrect option:

Option A:
Rennin is produced by stomach cells which digest coagulated milk proteins.
Option C:
Lipase is also present in the stomach where it digests milk fats and breaks them down in smaller fragments.

Option D:
Trypsin is present in the lumen of the small intestine and hence interacts later with digested food.

Final answer: The enzyme Pepsin carries on the initial step in the digestion of milk in humans.