Enzymes: Mechanism and Properties

This lesson covers the nature of enzymes, the lock and key and induced fit models of enzyme action, and the factors affecting enzyme activity, as required by the Edexcel A-Level Biology B specification (9BI0), Topic 1: Biological Molecules. You need to understand how enzymes work as biological catalysts, their specificity, and the effects of temperature and pH on their activity.

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What Are Enzymes?

Enzymes are biological catalysts — they speed up the rate of chemical reactions in living organisms without being permanently changed or consumed in the reaction.

Key Properties of Enzymes