1. Human digestive system Class XI

2. The Process of Digestion is accomplished by mechanical and Chemical process in different parts of the alimentary canal.

3. Alimentary canal consists of – 1. Buccal Cavity 2. Oesophagus 3. Stomach 4. Small Intestine 5.Large Intestine

4. 30% of the Starch is hydrolyzed by salivary amylase/Ptyalin at a pH of 6.8 into maltose.

5. 1. No digestion take place in Pharynx & Oesophagus. 2. Act as a Cannel through which the food passes into the stomach.

7. The gastric juice is a mixture of mucus, hydrochloric acid and protein digesting enzymes. (Pepsinogen and Pro-renin) Protien Proteoses and Peptones

8. 1. Duodenum receives biles, pancreatic juice and the intestinal juice. 2. Bile salts helps in the immlusification of fats and activate lipases. 3. Pancreatic juice contains – Trypsinogens, Chymotrysinogen Procarboxypeptides, Amylase Lipase and Nucleases.

10. ProteinTrypsinShorter polypeptides Peptones Proteoses Chymotrysin Shorter carboxypeptidases dipeptides polypeptides aminopeptidases Dipeptides dipeptidases Aminoacids

11. Lipids Lipases Diglycerides + (Triglycerides) Fattyacids Diglycerids Lipases Monoglycerides + Fattyacids Monoglycerides Lipases Fattyacids + Glycerol

12. QUESTION’S FOR SLOW LEARNER 1. What do you mean by digestion? 2.Name the enzyme present in human saliva. What is it’s pH? 3.In which part of alimentary canal, no digestion takes place?

13. QUESTION’S FOR AVERAGE LEARNER 1.What is the role of liver, gall bladder and pancreas in the digestion process ? 2. Why acidic environment in the stomach is needed for food digestion? 3. Which emzyme is requierd to digest milk proteins in the stomach of infants ?

14. QUESTION’S FOR BRIGHT LEARNER 1. In human, starch digestion starts in Buccal cavity but stops in the stomach. Why? 2. Why are villi present in ileum and not in the stomach ?