KS3 Science · Biology
Genetics and evolution
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Key words
Variation The differences between living things
Species A group of living things that can breed together to produce fertile offspring
Inherited variation Differences passed on from parents in their genes
Environmental variation Differences caused by surroundings and way of life
Continuous variation Can take any value in a range, such as height
Discontinuous variation Falls into separate groups, such as blood group
Heredity The passing of genetic information from one generation to the next
Gamete A sex cell: an egg or a sperm
Chromosome A thread of tightly coiled DNA that carries many genes
DNA The chemical that holds genetic information
Gene A section of DNA that controls an inherited feature
Double helix The shape of DNA: two strands twisted together
Mutation A change in the DNA
Natural selection The best-suited individuals survive, breed and pass on their genes
Evolution The change in a species over many generations
Extinct No individuals of the species are left alive
Biodiversity The variety of living things in a place
Gene bank A store of seeds, cells or other genetic material