Chapter 5 · Question 2

What is the role of acid in our stomach?

Back to Chapter
Q2

What is the role of acid in our stomach?

Answer Revealed
Direct Answer:
Hydrochloric acid in the stomach kills bacteria and provides an acidic medium for the enzyme pepsin to digest proteins.

Simple Explanation

Stomach acid kills germs and helps digest proteins by activating a special enzyme called pepsin.

Exam-Ready Structure

Hydrochloric acid present in the gastric juice performs several functions: it kills harmful bacteria present in food, activates the enzyme pepsin from its inactive form pepsinogen, and provides the acidic pH (around 2.0) necessary for pepsin to act on proteins and begin their digestion.

Key Points

  • Kills bacteria ingested with food
  • Activates pepsin enzyme
  • Provides acidic pH for protein digestion

Answer Sources

  • Stomach acid and pepsin
    textbook section | Science | Life Processes | Digestion in the stomach | Pages 7