Answer
A zymogen is a proenzyme or a precursor to an enzyme; it is an inactive protein that is converted to an active enzyme by the action of another enzyme. In the stomach the zymogen pepsinogen--secreted by the chief cells-- is converted into the active enzyme pepsin by hydrochloric acid which moves some of the amino acids of the zymogen protein
Work Step by Step
Other zymogens of the digestive tract are trypsinogen--which is converted to the active enzyme trypsin--,and chymotrypsinogen--which is activated to give the enzyme chymotrypsin.
