Hydrochloric Acid
- The stomach produces several fluids which together are known as gastric juice
- One of the fluids produced is hydrochloric acid
- This kills bacteria in food and gives a low pH for enzymes to work in the stomach
- Cells in the stomach lining are specially adapted to withstand the acidic conditions
How is a low pH helpful in the stomach?
- The low pH kills bacteria in food that we have ingested as it denatures the enzymes in their cells, meaning they cannot carry out any cell reactions to maintain life
- Pepsin, produced in the stomach, is an example of an enzyme which has a very low optimum pH - around pH 2
- The hydrochloric acid produced in the stomach ensures that conditions in the stomach remain within the optimum range for pepsin to work at its fastest rate
