3.Digestion in the stomach Gastric juice its secretion Nature,Compositions functions pH 0.9~1.5,colorless,1.5~2.5 L/day Hydrochloric acid (HCI) Secreted by parietal cells Basic secretion:0~5 mmol/h Max secretion:20~25 mmol/h Mechanism of HCI secretion Functions:see next page§ 3. Digestion in the stomach • Gastric juice & its secretion * Nature, Compositions & functions pH 0.9~1.5, colorless, 1.5~2.5 L/day Hydrochloric acid (HCl) Secreted by parietal cells Basic secretion: 0~5 mmol/h Max secretion: 20~25 mmol/h Mechanism of HCl secretion Functions: see next page