What is being taught lesson by lesson:

  • What is a species? Learn about the ways scientists classify living organisms.
  • Variation within a species. Analyse information about continuous and discontinuous variation.
  • Heredity. Looking into the kids of traits and looks that can be passed on from parents to their offspring.
  • Chromosomes, genes and DNA. A look into how the features that you found out about last lesson are passed onto offspring through genetic codes.
  • The DNA model. Look into how it was discovered and what is made from. Start to unlock the secrets of how this is an instruction manual for making living organisms.
  • Adaptations. Describe how organisms have evolved special features to make them more successful.
  • Natural selection and evolution. Look into the process described so famously by Charles Darwin. Look at what he saw and how this long process works.
  • Selective breeding. This is the process where organisms with a characteristic that is favourable is mated in order to pass on those wanted genes.
  • Extinction. This lesson is all about the study of what causes species to go extinct and what we can do to stop this happening.
  • Preservation of biodiversity. Look into the great work that conservationists and zoos do to preserve species that are on the verge of going extinct such as the work of Chester zoo.

Key Terms for this topic (Tier 3 vocabulary)

Organism – species – classification – heredity – genetic variation – environmental variation – chromosome – gene – adaptation – evolution – extinction.

KS3 Genetics & Evolution

Are you ready for your assessment in this topic? Try out this simple quiz.

What everyone needs to know:


  1. Understand what a species is.
  2. State what is meant by variation.
  3. State that children look like their parents because they inherit genes.
  4. Understand that some variation is genetic and some is environmental.
  5. State that genes are instructions for characteristics.
  6. State that genes are made of DNA.
  7. Understand that the work of many scientists contributed to our understanding of the structure of DNA.
  8. State what living things need in order to survive.
  9. Understand that organisms that are better adapted are more likely to survive to pass on their genes.
  10. State that selective breeding is used by farmers to breed animals with useful characteristics.
  11. State some reasons why an organism may become extinct.
  12. State some reasons why zoos and seed banks are set up.


  1. Describe how scientists classify organisms.
  2. Describe the difference between continuous and discontinuous variation.
  3. Explain why children look similar to their parents.
  4. Identify genetic and environmental variation.
  5. Describe the difference between DNA, genes and chromosomes.
  6. Describe the work of Watson, Crick, Wilkins and Franklin in the development of the DNA model.
  7. Describe how natural selection occurs.
  8. Describe how to use selective breeding to breed an animal with a desired characteristic.
  9. Understand what is meant by genetic modification.
  10. Link adaptation to extinction.
  11. Explain how zoos and seed banks help to prevent extinction and maintain Earth’s biodiversity.


  1. Explain why scientists classify organisms.
  2. Explain why siblings like similar but not identical.
  3. Apply the function of DNA to explain why people have different characteristics.
  4. Evaluate the importance of the discovery of the structure DNA.
  5. Explain how adaptations help an organism to survive.
  6. Explain how Darwin came up with his theory of evolution by natural selection.
  7. Evaluate the use of genetic modification and selective breeding.
  8. Evaluate the effects of extinction on the ecosystem.
  9. Evaluate the use of zoos and seed banks by thinking about their benefits and drawbacks.