IGCSE Biology / Life processes

Cells, tissues, organs and systems

Edexcel International GCSE Biology (4BI1), chapter 1: Life processes, specification point 2.1. Part of the full course.

Read the revision notes · IGCSE Biology past papers

Living organisms are organised in levels, from organelles inside cells to organ systems made of organs. Knowing the order and the difference between a tissue and an organ helps you identify and describe biological structures accurately.

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
• Enzymes and the active site