1. Proteins are extremely versatile in function and crucial in virtually all biological processes. 1.1 Almost all chemical reactions occurring in living organisms are catalyzed by enzymes. 1.1.1 Many thousands of enzymes have been discovered, each catalyzing a different kind of chemical reaction 1. 1.2 Life would not occur without enzyme catalysis. 1.1.3 Enzymes are the most varied and most highly specialized proteins.1.1 Almost all chemical reactions occurring in living organisms are catalyzed by enzymes. 1.1.1 Many thousands of enzymes have been discovered, each catalyzing a different kind of chemical reaction. 1.1.2 Life would not occur without enzyme catalysis. 1.1.3 Enzymes are the most varied and most highly specialized proteins. 1. Proteins are extremely versatile in function and crucial in virtually all biological processes