CAIE IGCSE Biology 7.4.5 Functions of hydrochloric acid
CAIE IGCSE Biology 7.4.5 Functions of hydrochloric acid
Practise explaining how hydrochloric acid in gastric juice supports stomach digestion through low pH and defence against microbes.
How this is tested
- explain how low stomach pH provides optimum conditions for pepsin activity
- state that hydrochloric acid kills harmful microorganisms in swallowed food
- interpret pH-enzyme graphs to link acidic optima with action in the stomach