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Functioning ecosystems and succession — Question 9

QCAA 2023, Paper 2 · 7 marks

Q9 · 2023 · Paper 2Unclassified7 marks

QUESTION 9 (7 marks)

The graphs show the findings of an experiment investigating the competitive exclusion principle. Two species of protozoa (P. aurelia and P. caudatum) were grown separately and together under identical conditions.

Biology question figure
Biology question figure

a) Identify the population density of P caudatum on day 10 when grown separately. [1 mark]

b) Compare the growth of P. aurelia in the two graphs. [3 marks]

c) Use the data to explain the competitive exclusion principle.

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