The Digestive System - The Stomach (T2)

Question 1

Describe in detail the stomach and the part it plays in the digestive system..

Answer 1

• carries out physical digestion, chemical digestion, storage and absorption of food
• food is held in the stomach for several hours, where protein digestion begins
• food is mixed with gastric juice containing hydrochloric acid and the enzymes pepsin and renin
• due to the hydrochloric acid, the stomachs pH is pH2
• the hydrochloric acid helps to begin protein digestion and it kills many harmful micro-organisms that may have been swallowed with the food
• the enzymes pepsin and renin work best at pH2
• once food has been chemically digested it is churned to form a liquid called chyme, which then enters the ‘duodenum’ (the first part of the small intestine)