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Continuity of life on Earth — Question 1

QCAA 2022, Paper 2 · 3 marks

Q1 · 2022 · Paper 2Unclassified3 marks

QUESTION 1 (3 marks)

This phylogenetic tree uses horizontal distance to represent genetic difference.

Biology question figure

$\mathrm{Scale}1 unit = nucleotide difference$

a) Infer which species is most closely related to species B. Explain your reasoning.

[2 marks]

b) Determine the genetic difference between species A and D.

[1 mark]

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