Question

Describe the functions of the stomach.

Answer 1

Hint: The stomach is the organ of the digestive system. It secretes enzymes to help in digestion. It acts as a temporary storage site for food as well.

Complete Answer:
The stomach is a J-shaped muscular organ located below the diaphragm in the abdominal cavity between the oesophagus and the small intestine. It is made up of multiple layers of tissue. It secretes digestive enzymes to help in food breakdown.
Anatomically, the stomach is divided into various regions. The fundus, the body, the antrum, and the pylorus. The fundus is the upper part of the stomach. The body is the largest part of the stomach. The antrum is the lower region, and the pylorus is the part that connects to the duodenum of the small intestine.
Layers of the Stomach:
The mucosa or mucous membrane of the stomach is replaced every few days and functions as a protective barrier from the hydrochloric acid released in the stomach.
The next layer is the submucosa, made up of connective tissue, nerve cells and fibres.
The muscularis is a three cell layer.
The serosa covers the outside of the stomach.
Functions:
The mucosa produces Hydrochloric acid which is protective in nature and also creates an acidic environment for the enzyme, Pepsin to function. It breaks down complex proteins in food to smaller peptides.
After this partial digestion, food is released into the small intestine. This release is controlled by a sphincter muscle called the pyloric sphincter.

Additional Information:
Pepsin is released by cells in the stomach called the chief cells.

Note:
Stomach ulcers are painful sores in the gastric lining, caused when the mucus lining of the stomach is reduced. When this happens, the hydrochloric acid that is released in the stomach starts eating away the inner lining of the stomach. This is curable, but without proper treatment they can be very severe.