Page 53 - CHAPTER 1 DIGESTION SYSTEM (2).pptx (Ebook Cover)

CHAPTER 2
2.2 Nutrient: protein, carbohydrate, fat, vitamin and mineral

Digestion,
Absorption

&
Metabolism

of Protein

Figure “Protein digestion in the human GI tract” by Alice Callahan is licensed under CC BY 4.0; edited from “Digestive
system diagram edit” by Mariana Ruiz, edited by Joaquim Alves Gaspar, Jmarchn is in the Public Domain

Protein digestion in GI Tract

Protein digestion takes place in the stomach and small intestine whereas
absorption of protein occur in small intestine..

In the small intestine, protease splits up protein into short peptide chains and
amino acids.
The brush border of the small intestine produce several peptidases, enzyme that
break down short peptide chains into amino acid, dipeptides and tripeptides.

When tripeptides and dipeptides enter the intestinal cells, they are split into amino
acids. As amino acids are water soluble, they travel easily in the blood to the liver
and then to the cells that need them.
Amino acids pool in the body provides the cells with a supply of amino acids

If the body already has enough glucose & energy, amino acids will be used in the
body by i) protein synthesis in cells around the body, ii) making other nitrogen
containing compounds, iii) rearranging & storing as fat and iv) making non
essential amino acids needed by protein synthesis,.
NUTRITION AND HEALTH 2023
Chapter 1 & 2 45