Stomach Digestion: Mechanical & Chemical Processes Explained

1. Mechanical digestion: The stomach churns and mixes food with gastric juices, breaking it down into smaller pieces. This process is aided by the muscular walls of the stomach and the presence of hydrochloric acid, which helps to soften the food.

2. Chemical digestion: The stomach also produces enzymes that begin to break down the proteins in food. The main enzyme involved in this process is pepsin, which is secreted in response to the presence of hydrochloric acid. Pepsin works best in an acidic environment, and it is able to break down proteins into smaller peptides.