1[1 mark]
All the individuals of one species living in the same area are called a
- community
- population
- ecosystem
- habitat
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Answer: B population (1)
2[2 marks]
State two abiotic factors that can affect a community.
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- temperature (1)
- light (1) allow light intensity
- water (1) allow water availability
- pollutants (1)
- Max 2
3[3 marks]
Two species of plant in a meadow need the same resources. Explain how competition between them could affect the number of each species.
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- both need the same limited resources, such as light, water or mineral ions (1)
- the better adapted species gets more of the resources, so grows and reproduces more (1)
- so the number of the other species decreases (1)
4[2 marks]
Explain why the organisms in a community are said to be interdependent.
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- organisms depend on other species for food / shelter / pollination / seed dispersal (1)
- so a change in the number of one species affects other species in the community (1)
5[4 marks]
Compare parasitism and mutualism. Give one example of each.
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- in parasitism the parasite benefits and the host is harmed (1)
- in mutualism both organisms benefit (1)
- parasitism example: tapeworm in human gut / flea on dog / any correct parasite (1)
- mutualism example: nitrogen-fixing bacteria in root nodules of legumes / cleaner fish / any correct example (1)