A. What is the role of hydrochloric acid in our stomach?

B. What is the function of enzymes in the human digestive system?

A. Hydrochloric acid kills the bacteria which enters the stomach and also makes the acidic medium in the stomach in which enzyme pepsin digests the proteins present in the food.

B. Different enzymes plays different roles in human digestive tract but their main function is to convert complex substances into simpler form for easy digestion of food. Like pepsin and trypsin digests the proteins, salivary amylase and amylase present in pancreatic juices digests starch and lipase digests the fats.