Question

Name the enzymes of pancreatic juice, the substrates they digest, and the end products.

Answer 1

The pancreatic juice contains proenzymes trypsinogen, chymotrypsinogen, procarboxy peptidase, pancreatic amylase, and pancreatic lipase.

(a) Digestion of proteins by pancreatic juice: Trysinogen converts into trypsin in the presence of enterokinase. Trypsin converts chymotrypsinogen into chymotrypsin; procarboxypeptidase into carboxy-peptidase; and peptones into peptides. Trypsin, chymotrypsin, and carboxy-peptidase act upon proteins. Chymotrypsin also converts peptones into peptides. Peptides get converted into smaller peptides and amino acids in the presence of carboxypeptidase.

Trypsin ogen \[\ce{->[Enterokinase][of interstinal juice]}\] Trypsin
Chymotrypsin ogen \[\ce{->[Trypsin]}\] Chymotrypsin
Procarboxypep tidase \[\ce{->[Trypsin]}\] Carboxy - peptidase
Peptones \[\ce{->[Trypsin]}\] Peptides
Peptones \[\ce{->[Chymotrypsin]}\] Peptides
Peptides \[\ce{->[carboxypeptidase]}\] Smaller Peptides + Amino acid

(b) Digestion of carbohydrates by pancreatic juice: Pancreatic amylase acts upon starch in the presence of chlor ide ions and converts it into maltose, isomaltose and dextrin.

Starch \[\ce{->[Pancreatic][Amlylase + Cl-]}\] Maltose + Isomaltose + Limit dextrin.

(c) Digestion of fats: Pancreatic juice contains pancreatic lipase which emusifies the fats into fatty acids and glycerol.

Emulsified fat\[\ce{->[Pancreatic][lipase]}\] Fatty acid+ Glycerol