The stomach is the principal organ that breaks down food as it enters the digestive system. Digestion is the disintegration of insoluble food molecules into small water-soluble food molecules so they can be absorbed into the watery blood plasma. The stomach plays a significant role in digestion.
While it serves as a temporary reservoir of foods, it also participates in the control of appetite, digestion, and the absorption of food. Stomach acid will encourage the production of mucus to protect the cell wall from being damaged by hydrochloric acid.