Study of the structure,function and how they work of body parts ,

1. Anatomy and Physiology
Sabu.VU,
sabuvayalarikil@gmail.com
MBA, DMS (HMA)

11. Digestive system
 Mouth
The oral cavity or the mouth contains salivary glands that secrete a wide
range of enzymes to aid the first step of metabolism of food. 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. The list of
digestive enzymes secreted by the oral cavity are mentioned in the table.
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

12. Stomach
The enzymes released by the stomach are known as gastric enzymes. They are
responsible for breaking down complex macromolecules like proteins and fats into
simpler compounds. Pepsinogen is the main enzyme of the stomach and its active
form is pepsin. Stomach secretes hydrochloric acid which kills bacteria and germs and
provides an acid environment for proper enzymatic activity of protease enzymes. The
list of digestive enzymes secreted by the stomach are mentioned below.
Enzymes Function
Pepsin Breaks protein into small peptides
Gastric amylase Degradation of starch
Gelatinase Degradation of gelatin and collagen present as proteoglycans in meat
Rennin Conversion of liquid milk to solid particles
Gastric lipase Degradation of butter fat

13. Pancreas
It functions both as an endocrine and exocrine gland. The digestive enzymes secreted by
pancreas are listed in the table.
Enzymes Function
Pancreatic lipase- Degrades triglycerides into fatty acids and glycerol
Phospholipase Hydrolyzes- phospholipids into fatty acids and lipophilic substances
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

14. 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.
This takes place just prior to excretion. The food gets converted to semi-solid
form by the activity of the enzymes present in the duodenum, jejunum, and
ileum. The enzymes functioning in this part of the digestive system are
mentioned below.
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