Edexcel GCSE Combined Science, topic 4
Natural selection and genetic modification
This topic explains how populations change over time by natural selection, and the evidence for evolution, including human evolution. It then covers the ways humans change organisms for their own use: selective breeding, tissue culture and genetic engineering.
Revision notes
Worksheet
FlashcardsSubtopics
Work through them in order. Each one has notes, exam questions and flashcards, and a PDF of each. Triple-only subtopics are left out.
- 1Darwin, natural selection and antibiotic resistance Spec 4.1B–4.3How Darwin and Wallace developed the theory of evolution by natural selection, and how antibiotic-resistant bacteria support it.NotesQuestions 6Flashcards 10
- 2Evidence for evolution and classification Spec 4.4–4.7Fossil and stone tool evidence for human evolution, the pentadactyl limb, and how genetic analysis led to the three domains.NotesQuestions 7Flashcards 13
- 3Selective breeding and tissue culture Spec 4.8–4.9BHow selective breeding changes food plants and domesticated animals, and how tissue culture makes identical plants and cells.NotesQuestions 6Flashcards 9
- 4Genetic engineering Spec 4.10–4.12BWhat genetic engineering is, the main stages using restriction enzymes, ligase and vectors, and GM crops such as Bt crops.NotesQuestions 6Flashcards 10
- 5Agriculture and evaluating biotechnology Spec 4.13B–4.14Fertilisers and biological control for a growing population, and the benefits and risks of genetic engineering and selective breeding.NotesQuestions 4Flashcards 9
Whole topic
When you have done the subtopics: test yourself on everything, or print the lot.