Final answer:
Inhibitory peptides are released from pepsinogen by hydrochloric acid (HCl), freeing the fully active enzyme pepsin. Converting it to the active enzyme pepsin, which plays a crucial role in the digestion of proteins in the stomach.
Step-by-step explanation:
Inhibitory peptides are released from pepsinogen by the action of hydrochloric acid (HCl), freeing the fully active enzyme pepsin. This process is crucial in protein digestion, which primarily takes place in the stomach. Pepsinogen is an inactive enzyme (zymogen) secreted by the chief cells located in the stomach wall. Upon exposure to the acidic environment of the stomach, where the pH levels range between 1.5 and 2.5, pepsinogen undergoes an autocatalytic conversion to its active form, pepsin.
Pepsin is a proteolytic enzyme that specializes in breaking down peptide bonds, particularly those involving aromatic amino acids like tyrosine, tryptophan, and phenylalanine, as well as methionine and leucine, resulting in smaller peptide fragments. These peptides are then further digested in the small intestine by enzymes like trypsin and chymotrypsin that are released by the pancreas and activated by enterokinase found in the small intestine wall.