(N/A) The enzyme trypsin (present in the pancreatic juice) activates the inactive enzyme chymotrypsinogen into chymotrypsin.
$\text{Chymotrypsinogen (Inactive)} \xrightarrow{\text{Trypsin}} \text{Chymotrypsin (Active)}$
The activated chymotrypsin plays an important role in the further breakdown of partially-hydrolysed proteins into peptides.
$\text{Proteins} \xrightarrow{\text{Chymotrypsin}} \text{Peptides}$
The other digestive enzymes of the same category (proteases) secreted by the pancreas are trypsinogen and carboxypeptidase.
Trypsinogen is present in an inactive form in the pancreatic juice. The enzyme enterokinase,secreted by the intestinal mucosa,activates trypsinogen into trypsin.
$\text{Trypsinogen} \xrightarrow{\text{Enterokinase}} \text{Trypsin} + \text{Inactive peptide}$
The activated trypsin then further hydrolyses the remaining trypsinogen and activates other pancreatic enzymes such as chymotrypsinogen and carboxypeptidase. Trypsin also helps in breaking down proteins into peptides.
$\text{Proteins} \xrightarrow{\text{Trypsin}} \text{Peptides}$
Carboxypeptidases act on the carboxyl end of the peptide chain and help in releasing the last amino acids.
$\text{Peptides} \xrightarrow{\text{Carboxypeptidase}} \text{Small peptide chain} + \text{Amino acids}$