What is Stomach?
The stomach is a muscular organ that receives the food from the oesophagus. Its main function is to digest the food we eat.
Stomach
What are the Roles of the stomach?
There are two major roles of the stomach: breakdown of food and storage of food.
- Digestion of food
● The physical breakdown of food
- The muscles of the stomach contract and churn the
- The inner layer of the stomach is full of wrinkles known as Rugae. They help to grip and move food during
- The Churning aids in the conversion of Bolus to Chyme. Chyme is a milky paste formed after the stomach digest the
● The chemical digestion of food
- The chemical breakdown occurs in the presence of Gastric Enzymes.
- These enzymes are present in the gastric juices secreted by the Gastric Glands.
- These glands are present in the lining of the
- Three enzymes mainly cause chemical digestion of the food:
■ Hydrochloric acid
Hydrochloric acid kills the bacteria in the food and protects our body. This acid also creates ideal conditions for Pepsin to act on the food.
Hydrochloric acid is highly acidic, strong enough to dissolve metal. Our stomach has a Layer of Mucus that protects the lining of the stomach from hydrochloric acid.
■ Pepsin
The pepsin helps in the enzymatic breakdown of Proteins into peptides.
■ Gastric lipase
Gastric lipase helps in digestion of Fats.
(ii) Storage bag
The stomach can hold around 2 to 3 litres of chewed up food. This allows us to consume a large meal quickly and then digest it over an extended period.