Protein Digestion Flashcards
Does any protein digestion occur in the mouth? Explain why/why not.
No protein digestion takes place in the mouth, as the mouth does not contain any enzymes that break down proteins into individual amino acids.
Stomach acid contains strong acid hydrochloric acid (HCl). How does HCl assist protein digestion?
HCl is highly acidic, which allows the HCl to DENATURE the dietary proteins - makes it easier for enzymes to break the peptide bonds which join the amino acids.
HCl also ACTIVATES the pepsinogen enzyme into the active pepsin form, which can break peptide bonds within proteins.
What enzyme(s) help facilitate protein digestion in the stomach? What do these enzymes do that assists breaking down proteins into amino acids?
The PEPSINOGEN enzyme is present in the stomach.
It’s activated to become PEPSIN and break peptide bonds within proteins.
Pepsin progressively chops the protein into smaller and smaller chains of amino acids (by breaking the peptide bonds between amino acids).
What enzyme(s) help facilitate protein digestion in the small intestine? What do these enzyme do that assists breaking down proteins into amino acids?
The protease enzymes trypsinogen and chymotrypsinogen are released by the pancreas into the small intestine.
They are activated to become trypsin and chymotrypsin and they chop the protein into smaller and smaller chains of amino acids (by breaking the peptide bonds between amino acids).
Eventually, only single amino acid remains, as all of the peptide bonds have been broken.
What breakdown product of dietary protein is absorbed by the small intestine? Where is this breakdown product taken next (via the blood)?
Once broken into single amino acids (peptide bonds broken) the AAs can be absorbed by the small intestine.
Once in the blood, they can be taken to cells that require the amino acid to build new proteins that the cells require (via translation).
