Enzymes

Chapter Overview

Class 11 Biology Chapter 3, 'Enzymes', provides an in-depth exploration of biocatalysts, explaining how they accelerate vital biochemical reactions without being consumed. The chapter breaks down enzyme structure, focusing on the active site components (binding and catalytic sites), along with cofactors (prosthetic groups, coenzymes, and activator ions). It outlines the mechanism of action, comparing the Lock and Key Model with the induced-fit model, and explains activation energy lowering.

Students will examine critical factors affecting enzyme reaction rates, including temperature (optimum temperature and denaturation), pH variations, and substrate and enzyme concentrations. It also details enzyme inhibition, classifying inhibitors into competitive (competing for the active site) and non-competitive (binding to an allosteric site), as well as explaining the regulatory process of feedback inhibition.

The chapter concludes with enzyme classification systems based on reaction types (such as oxidoreductases, transferases, hydrolases, lyases, isomerases, and ligases) and substrates (proteases, lipases, carbohydrases, nucleases). It also features a real-world STEAM activity on Enzyme Engineering, demonstrating how immobilized enzymes are used to create lactose-free milk. These notes summarize these concepts into clear, SLO-oriented resources.