Which of the Following is NOT an Example of a Zymogen

Question

Which of the following is NOT an example of a zymogen and its activating protease?
A)chymotrypsinogen and chymotrypsin
B)proinsulinc and insulin
C)pepsinogen and pepsin
D)trypsinogen and trypsin

Accepted Answer

Proinsulin is a precursor to insulin and is not activated by a protease. Rather, it undergoes post-translational modifications, including cleavage by endopeptidases, to form the active insulin molecule. The other options are all examples of zymogens and their corresponding activated proteases.