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Functioning ecosystems and succession — Question 20

QCAA 2021, Paper 1 · 1 mark

Q20 · 2021 · Paper 1Unclassified1 mark

QUESTION 20

A keystone species is defined as a species that

(A) is the top predator in an ecosystem.

(B) is a major producer in an ecosystem.

(C) has a unique and crucial role in an ecosystem.

(D) directly influences all species in an ecosystem.

References

Question 10 Adapted from OpenStax 2018, Figure 6 in ‘OpenStax Biology 2e’, Lumencandela, available at https://courses.lumenlearning.com/suny-osbiology2e/chapter/understanding-evolution/. Licensed under CC BY 4.0.

© State of Queensland (QCAA) 2021 Licence: https://creativecommons.org/licenses/by/4.0 | Copyright notice: www.qcaa.qld.edu.au/copyright — lists the full terms and conditions, which specify certain exceptions to the licence. Third-party materials referenced above are excluded from this licence. | Attribution: © State of Queensland (QCAA) 2021

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