This document discusses key concepts around biochemical processes and enzymes. It defines metabolism as thousands of chemical reactions in organisms that give off heat depending on metabolic rate. Catabolic reactions break down complex molecules into simpler ones, releasing energy. Anabolic reactions join atoms and molecules to build complex structures and require energy. Reactions are controlled by biochemical pathways using enzymes. Mitochondria produce ATP through energy-releasing reactions. Enzymes are biological catalysts that speed up chemical reactions using specific active sites without being used up in the process. Factors like pH, temperature, enzyme and substrate concentrations can affect enzyme activity.

1. Chapter 3 Nature of Biochemical Processes

13. Induced fit

14. Lock and key

16. Activation energy