Stomach- Choon Wee & Afif

• Stomach 
• Type of digestion : 
• Chemical
  Physical
• Enzymes
• Pepsin
• Digest proteins
• 
  
• Product : Polypeptide
• Processes that take place in the stomach 
• Presence of food causes the gastric glands to secrete gastric juice into the stomach cavity
• Peristalsis in the stomach wall churns and breaks up the food.
  Peristalsis also mixes the food well with gastric juice
• Acid stops the action of salivary amylase by denaturing it
• Changes the inactive form of the enzyme pepsinogen, in the gastric juice to the active form called pepsin 
• Acid kills certain potentially harmful micro organisms in the food. 
• Stomach has a mucus layer that protect the stomach wall from the acid 
• *Renin that 'curdles' the substance so that there would be more time for digestion 
• Adaptation 
• Thick well developed muscular walls
• Stomach wall has numerous pits which leads to gastric glands that secretes gastric juice 
• There is a ring of muscle called the pyloric sphincter located at the place where the stomach joins the small intestine. When this ring contracts, the entrance to the small intestine closes.