19. Enzymes

Match the terms (a) allosteric control, (b) feedback control, (c) zymogen activation, and (d) phosphorylation/dephosphorylation with each of the following:

_______ Proline inhibits glutamate 5-kinase, the enzyme in the first step of the biosynthesis of proline from glutamate. 

_______ Glycogen synthase loses its catalytic activity when it is phosphorylated.

_______ Proelastase is converted to its active form elastase when it loses some part of its polypeptide backbone.

_______ Adenosine monophosphate binds to phosphofructokinase-1 and increases its activity.

Match the terms (a) allosteric control, (b) feedback control, and (c) zymogen activation with each of the following:

_______ Pepsinogen is converted into its active form (pepsin) by losing 44 amino acids from its primary structure.

_______ A small molecule attaches to the enzyme and makes an active site available to a substrate.

_______ The end-product of a metabolic pathway decreases the activity of the enzyme in the first step.

_______ Alanine binds to pyruvate kinase and reduces active site availability for the enzyme's substrate.