Digestive enzyme: Difference between revisions

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Enzymes are also in your mouth, helping to break down food, as well as the teeth are.
Enzymes are also in your mouth, helping to break down food, as well as the teeth are.


u are a bitch
==Stomach==
The enzymes that get secreted in the [[stomach]] are called '''gastric enzymes'''. These are the following:
*[[Pepsin]] is the main gastric enzyme. As it breaks [[protein]]s into smaller [[peptide]] fragments, it is a [[peptidase]].
*[[Gelatinase]], degrades type I and type V [[gelatin]] and type IV and V [[collagen]], which are [[proteoglycan]]s in meat.
*[[Amylase|Gastric amylase]] degrades starch, but is of minor significance.
*[[Lipase|Gastric lipase]] is a [[tributyrase]] by its biochemical activity, as it acts almost exclusively on [[tributyrin]], a butter fat enzyme.


==Small intestine==
==Small intestine==

Revision as of 19:09, 7 November 2008

Digestion enzymes are enzymes that break down polymeric macromolecules into their smaller building blocks. Digestive enzymes are found in the digestive tract of animals where they aid in the digestion of food as well as inside cells, especially in their lysosomes.

Digestion enzymes are classified by their substrates: proteases and peptidases split proteins into amino acids, lipases split fat into fatty acids, carbohydrases split carbohydrates such as starch into sugars, and nucleases split nucleic acids into nucleotides.

In the human digestive system, the main sites of digestion are the oral cavity, the stomach, the duodenum, and the jejunum and digestive enzymes are secreted by different glands: the salivary glands, the glands in the stomach, the pancreas, and the glands in the small intestines.

Oral cavity

In the oral cavity, salivary glands secrete ptyalin. It is a type of α-amylase, which digests starch into small segments of multiple sugars and into the individual soluble sugars. Secreted by small and large salivary glands.

Salivary glands also secrete lysozyme, which kills bacteria but is not classified as a digestive enzyme.

Summary of the actions of digestive enzymes:

Enzymes are also in your mouth, helping to break down food, as well as the teeth are.

u are a bitch

Small intestine

Pancreatic enzymes

The pancreas is the main digestive gland in our body. It secretes the enzymes:

Proper small intestine enzymes

Five types of enzymes degrade disaccharides into monosaccharides:

The small intestine receives lipase, trypsin and amylase from the pancreas. They are transported from the pancreas to the duodenum through the pancreatic duct. Protein, fats and starch are broken down into smaller molecules. However, they are not fully broken down yet. This causes the enzymes of the small intestine to act upon them. These enzymes include peptidase, which breaks down peptides into amino acids and the enzyme maltase acts upon maltose which produces glucose. These molecules are absorbed by the villi in the small intestine and according to the molecule they are either absorbed by the lacteal or blood capillaries.

References