What is the primary function of hydrochloric acid in the stomach of humans?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is Option 3: To create an acidic medium for enzyme action
Explanation:
- In the human stomach, hydrochloric acid (HCl) is secreted by the gastric glands. Its primary functions are as follows:
- Enzyme Activation: The stomach contains an enzyme called 'pepsin,' which digests proteins. This enzyme exists in an inactive state (as pepsinogen). HCl creates an acidic medium that converts pepsinogen into active pepsin.
- Destruction of Harmful Germs: This acid destroys harmful bacteria and microorganisms that enter the body along with food, thereby providing protection against infections.
- Softening of Food: It helps in breaking down food into smaller pieces and softening it to facilitate easier digestion.
Key Components of the Digestive System (Quick Revision):
- Mucus: A layer of mucus covers the inner lining of the stomach to protect it from the harmful effects (irritation/burning) of HCl.
- Bile Juice: This is secreted by the liver and renders the acidic food arriving from the stomach alkaline, allowing pancreatic enzymes to function effectively.
- pH Value: Due to the presence of HCl in the stomach, the pH of the medium ranges approximately between 1.5 and 3.5, which is highly acidic.
Important Questions for Upcoming Exams:
Question: Which substance is responsible for protecting the walls of the stomach from burning?
Answer: Mucus.
Question: In which part of the body is the enzyme pepsin found?
Answer: The Stomach.
Question: Where does the digestion of proteins primarily begin?
Answer: In the stomach.