Question

What are the enzymes involved in digestion of humans?
Mention their functions.

Answer 1

The oral cavity or the mouth contains salivary glands. The salivary gland secretes the enzyme lysozyme which has an antibacterial action. The enzymes secreted by the mouth mainly provide protection against bacteria. Betaine helps to maintain a fluid balance inside the mouth.

Enzymes & Function:
Ptyalin- Converts starch to simple soluble sugars
Amylase- Converts starch to soluble sugars
Betaine- Maintains cell fluid balance as osmolytes
Bromelain- Anti-inflammatory agent, tenderizes meat

Stomach
The enzymes released by the stomach are known as gastric enzymes. Stomach secretes hydrochloric acid which kills bacteria and germs and provides an acid environment for proper enzymatic activity of protease enzymes.

Enzymes & Function:
Pepsin- Breaks protein into small peptides
Gastric amylase- Degradation of starch
Gelatinase- Degradation of gelatin and collagen
Rennin- Conversion of liquid milk to solid particles
Gastric lipase- Degradation of butter fat

Pancreas
Pancreas is the main digestive gland of our body. The digestive enzymes of the pancreas breakdown carbohydrates and starch molecules to simple sugars. They also secrete a group of enzymes which help in degradation of nucleic acids. It functions both as an endocrine and exocrine gland.

Enzymes & Function:
Pancreatic lipase- Degrades triglycerides into fatty acids and glycerol
Phospholipase- Hydrolyzes phospholipids into fatty acids
Trypsin- Converts proteins to basic amino acids
Steapsin- Breakdown of triglycerides to glycerol and fatty acids
Chymotrypsin- Converts proteins to aromatic amino acids
Carboxypeptidase- Degradation of proteins to amino acids
Pancreatic amylase- Degradation of carbohydrates to simple sugars
Elastases- Degrade the protein elastin
Nucleases- Conversion of nucleic acids to nucleotides and nucleosides

Small Intestine
The final step of digestion is carried out by the small intestine. It contains a group of enzymes that breakdown the products undigested by the pancreas.The food gets converted to semi-solid form by the activity of the enzymes present in the duodenum, jejunum, and ileum.

Enzymes & Function:
Sucrase- Converts sucrose to disaccharides and monosaccharides
Maltase- Converts maltose to glucose
Lactase- Converts lactose to glucose and galactose
Isomaltase- Converts maltose to isomaltose
After knowing the types of digestive enzymes and their respective functions, I hope you understand how intricately the human digestive system works. The final product of digestion i.e. feces is then transported to the large intestine from where it is expelled.