Question

Select all chemicals that directly perform PROTEIN digestion.

	lastase
	micelles
	carboxypeptidase
	enterokinase
	ribonuclease
	peptide YY
	chymotrypsin
	zymogens
	gastric inhibitory peptide
	gastrin
	galanin
	acetylcholine
	HCl
	deoxyribonuclease
	bilirubin
	trypsin
	epinephrin
	sucrase
	insulin
	ghrelin
	leptin
	intrinsic factor
	dipeptidase
	cholecystokinin
	lipase
	glucagon
	maltase
	bile acids/salts
	amylase
	pepsin
	nucleosidases
	bicarbonate buffer
	aminopeptidase

Answer 1

The chemicals which directly perform protein digestion are:

• Carboxypeptidase ( it is secreted by pancreas and hydrolyzes first peptide bond at c-terminal in the small intestine)
• Chymotrypsin( it is also secreted by pancreas)

* zymogens are proenzymes like chymotrypsinogen and trypsinogen which gets converted into active forms, chymotrypsin and trypsin to digest proteins. Thus they are not directly involved.

• Trypsin( active form of trypsinogen)
• Dipeptidase ( breaks dipeptides into individual amino acids)
• Pepsin ( secreted by chief cells of stomach)
• Aminopeptidase( breaks peptide bond at amino or N-terminal)