Page 159 - Knowledge Organiser Yr8 24-25

Knowledge Base: Science 8.14 Variation Year 8
6. Natural Selection and Evolution
6.1
What does variation between species and individuals of the same species cause?
Some organisms to compete more successfully than others
7. Maintaining Biodiversity
7.1
What is biodiversity?
A measure of the range of living organisms within a habitat
6.2 What is natural selection?
A process by which a species changes over time
7.2 What is a gene pool?
The range of DNA in a species
7.3
What is deforestation and why is it done?
The removal of forests, often to make space for farming, industry, settlements, roads and use of wood and fuel
7.4
What is conversation?
The process that preserves and protects organisms and their habitats and so maintains biodiversity
7.5
Give three methods humans are using to maintain biodiversity
Zoos and breeding programmes, protecting areas using national parts, and reducing the use of fossil fuels.
6.3
Give the two factors that natural selection happens in response to
Changes in the environment or competition between organisms
6.4
Describe the process of natural selection
The members of the species with the most desirable characteristics for their environment are most likely to survive and reproduce.
6.5
What happens if a species is unable to adapt?
They become extinct
6.6
Give 4 reasons species may need to adapt
New predators, new diseases, destruction of habitats, increased competition for resources.
6.7
Describe how natural selection leads to evolution
1. Individual organisms with the best adaptations are most likely to survive and reproduce.
2. Inheritance means these adaptations are likely to be passed to offspring
3. Less adapted organisms are less likely to pass on their adaptations
4. Over many generations small differences add up to the formation of a new species by evolution
8. Extinction
8.1 What is extinction?
When all organisms of a species dies out
8.2
How does extinction happen?
When organisms are unable to adapt to their environment and therefore do not compete successfully and do not reproduce.
8.3
How can we protect species from extinction?
Preserve genetic material for use in the future using gene banks
8.4
Give 2 examples of gene banks
Seed banks and cryobanks
6.8 Give one cause of variation
Small changes in DNA called mutations
6.9
Who first proposed the theory of evolution?
Charles Darwin
6.10
Why was it many years before the theory of evolution was published?
The theory challenged religious ideas about evolution
6.11
What do scientists' study as evidence for evolution?
Fossil records
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