Topic 4: Natural selection and genetic modification – GCSE Edexcel Higher Biology revision notes

What this topic covers

Topic 4: Natural selection and genetic modification has 5 subtopics:

• Variation and evolution
• The development of understanding of genetics and evolution
• Classification of living organisms
• Food production (biology only)
• Additional Edexcel Topic 4 anchors

Topic 4: Natural selection and genetic modification lessons by subtopic

30 lessons, grouped by subtopic.

Variation and evolution

• What is Evolution?
• How Evolution Works Through Natural Selection
• Formation of New Species
• What is Selective Breeding and How Does it Work?: Understand the process of selective breeding and learn about examples including disease-resistant crops, high-yield animals, gentle dogs, and decorative flowers.
• The Impact and Problems of Selective Breeding: Explore the benefits and drawbacks of selective breeding, including its impact on food production and the problems of inbreeding in domesticated animals.
• The Process of Genetic Engineering
• Applications of Genetic Engineering
• Benefits, Risks and Ethics of Genetic Engineering
• Animal Cloning Techniques
• Plant Cloning Methods

The development of understanding of genetics and evolution

• Darwin's Theory of Natural Selection
• The Publication and Controversy of Evolution: Examine the publication of 'On the Origin of Species' in 1859, the controversy it caused by challenging religious beliefs, and why the theory faced initial resistance from the scientific community.
• Comparing Theories of Evolution: Compare Darwin's theory of natural selection with alternative theories like Lamarck's theory of inheritance of acquired characteristics, and understand why Darwin's theory is now accepted.
• Darwin and Wallace: Developing the Theory of Evolution
• Wallace's Contributions and the Impact on Biology
• The Process of Speciation
• Evidence for Evolution: Explore the key evidence that supports the theory of evolution, including fossil records and antibiotic resistance in bacteria. Learn how these examples demonstrate evolutionary processes in action.
• Darwin's Theory and Modern Evidence: Understand how Darwin's theory of evolution by natural selection became widely accepted and examine the modern evidence that supports it, including genetic inheritance and bacterial resistance.
• What are fossils and how are they formed?
• Fossils as evidence for evolution
• Understanding Extinction and Its Causes: Students will learn what extinction means and explore the various factors that can lead to species becoming extinct, including environmental changes, human activities, and natural disasters.
• How Antibiotic Resistance Develops: Learn how bacterial evolution and mutations lead to antibiotic-resistant strains, including the role of rapid reproduction and natural selection in creating superbugs like MRSA.
• Preventing Antibiotic Resistance: Explore strategies to reduce antibiotic resistance including appropriate prescribing by doctors, completing antibiotic courses, and restricting agricultural use, plus the challenges of developing new antibiotics.

Classification of living organisms

• The Three-Domain System
• The Linnaean Classification System
• Evolution of Classification and Evolutionary Trees

Food production (biology only)

• Biotechnology Solutions for Food Production
• GM Crops and Improved Nutrition

Additional Edexcel Topic 4 anchors

• Tissue culture in plant breeding: Explore tissue culture and cuttings - two techniques used to produce identical plants for commercial and conservation purposes.
• Agricultural solutions and genetic engineering evaluation: Evaluate fertilisers, biological control, selective breeding and genetic engineering as agricultural responses.

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More in this course

Go back to the full GCSE Edexcel Higher Biology topic list, or practise this topic with past-paper questions.