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Revision notes
IGCSE
Biology
Edexcel IGCSE
Higher
Eye - Focusing

Eye - Focusing

Biology: Edexcel IGCSE, topic 3.5.12

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Previous topic3.5.11 The Eye Next topic3.5.13 Eye - Adapting to Light

Biology: Edexcel IGCSE contents

1 The Nature & Variety of Living Organisms
- 1.1 Characteristics of Living Organisms
  1.1.1 MRS GRENC
  1.1.2 M.R.S.
  1.1.3 G.R.E.N.C.
- 1.2 Variety of Living Organisms
  1.2.1 Types of Cells
  1.2.2 Properties of Prokaryotes
  1.2.3 Structure of Eukaryotic Cells
  1.2.4 Organisms: Animals & Plants
  1.2.5 Other Kingdoms
  1.2.6 Pathogens
  1.2.7 Viruses
2 Structure & Functions in Living Organisms
3 Organism Functions
4 Reproduction & Inheritance
5 Ecology
- 5.1 Ecosystems
  5.1.1 Ecosystems
  5.1.2 Resources
  5.1.3 Interdependence
  5.1.4 Growth Factors
  5.1.5 Assessing Ecosystems
  5.1.6 Quadrats
  5.1.7 Required Practical
  5.1.8 Exam-Style Questions - Sampling
  5.1.9 Energy Flow
  5.1.10 Food Chains
  5.1.11 Trophic Levels
  5.1.12 Decomposers
  5.1.13 Pyramids of Biomass
  5.1.14 Transfer of Biomass
  5.1.15 Reasons for Wastage
  5.1.16 End of Topic Test - Food and Trophic Levels
  5.1.17 Recycling Materials
  5.1.18 Carbon Cycle
  5.1.19 Exam-Style Questions - Carbon Cycle
  5.1.20 Nitrogen Cycle
  5.1.21 The Nitrogen Cycle and Microorganisms
  5.1.22 End of Topic Test - Ecosystems
  5.1.23 Grade 9 - Ecosystems
- 5.2 Human Impacts
  5.2.1 Waste Management
  5.2.2 Eutrophication
  5.2.3 Air Pollution
  5.2.4 Deforestation
  5.2.5 The Greenhouse Effect
  5.2.6 Greenhouse Gases
  5.2.7 Global Warming
  5.2.8 End of Topic Test - Human Impacts
  5.2.9 Exam-Style Questions - Air Pollution
6 Biological Resources
- 6.1 Food Production
  6.1.1 Intensive Farming - Crop Yield
  6.1.2 Intensive Farming - Ion Deficiency
  6.1.3 Intensive Farming - Pest Control
  6.1.4 Intensive Farming - Fish Farming
  6.1.5 Microorganisms in Food
  6.1.6 Factors Affecting Microorganism Growth
  6.1.7 Industrial Fermentation
  6.1.8 Selective Breeding
  6.1.9 Selective Breeding Process
  6.1.10 Uses of Selective Breeding
  6.1.11 Exam-Style Questions - Selective Breeding
- 6.2 Genetic Engineering
  6.2.1 Genetic Engineering
  6.2.2 Uses of Genetic Engineering
  6.2.3 Producing Human Proteins in Bacteria
  6.2.4 Tissue Culture
  6.2.5 Uses of Tissue Culture
  6.2.6 Artificial Animal Cloning
  6.2.7 Exam-Style Questions - Mitosis & Cloning

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