Hint: It's an endopeptidase that breaks down a building block of the body into smaller peptides. It's produced within the chief cells of the stomach lining and is one among the most digestive enzymes within the digestive systems of humans and lots of other animals, where it helps digest the proteins in food.
Pepsin is produced within the stomach and is one of the most digestive enzymes within the digestive systems of humans and lots of other animals, where it helps digest the proteins in food. Zymogenic cell or peptic cell may be a cell within the stomach that releases pepsinogen and chymosin.
The proenzyme pepsinogen(inactive) , on introduction to corrosive, gets changed over to the dynamic compound pepsin. Pepsin hydrolyses proteins to polypeptide chains and starts protein assimilation inside the absorption cycle in people. Hence, the pepsin digests protein within the stomach.
Additional information: Pepsin is expressed as a zymogen called pepsinogen, whose primary structure has a further 44 amino acids compared to the active enzyme.
In the stomach, chief cells release pepsinogen. This zymogen is activated by acid (HCl) , which is released from parietal cells within the stomach lining. The hormone gastrin and therefore the vagus triggers the discharge of both pepsinogen and HCl from the stomach lining when food is ingested.
The acid establishes an acidic climate, which permits pepsinogen to unfurl and separate itself in an autocatalytic manner, along these lines creating pepsin (the dynamic structure) . Pepsin cleaves the 44 amino acids from pepsinogen to make more pepsin.
So the correct answer is ‘(a) Proteins in the stomach’.
Note: Commercial pepsin is extracted from the glandular layer of hog stomachs. it's a component of rennet wont to curdle milk during the manufacture of cheese. Pepsin is employed for a spread of applications in food manufacturing: to switch and supply whipping qualities to soy protein and gelatin, to switch vegetable proteins to be used in non-dairy snack items, to form precooked cereals into instant hot cereals, and to organize animal and vegetable protein hydrolysates to be used in flavoring foods and beverages.