1. Mechanical digestion: storage, mixing & liquefaction of bolus of food into chyme
2. Secretion: 300 ml of gastric juice composed of mucus, HCl, pepsinogen and water
3. Chemical digestion: digestion of protein starts through pepsin, amylase inactivated by acidity, pepsinogen converted to pepsin by HCl, milk curdled by rennin, emulsified fats digested by gastric lipase
4. Protection: acid medium reduces activity of harmful bacteria, provides medium for absorption of calcium and other minerals
5. Absorption: minimal water, alcohol, glucose & some drugs absorbed through gastric mucosa
6. Control passage of chyme into duodenum through peristaltic waves