IGCSE Biology / Life processes

Enzymes and the active site

Edexcel International GCSE Biology (4BI1), chapter 1: Life processes, specification point 2.10. Part of the full course.

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Enzymes are proteins that speed up reactions without being used up. Their active site has a complementary shape to a particular substrate, which explains why each enzyme carries out a specific job.

More lessons in Life processes

• The characteristics of living organisms
• Animal and plant cells under the microscope
• The light microscope and magnification
• Temperature, pH and denaturing
• Practical: measuring enzyme activity
• Anaerobic respiration and how it differs from aerobic
• Practical: enzymes and food
• Aerobic respiration and ATP
• Practical: showing that respiring seeds give out carbon dioxide and heat
• Diffusion
• Osmosis
• Active transport
• What changes the rate of movement
• Stem cells and differentiation
• Cells, tissues, organs and systems