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Continuity of life on Earth — Question 20

QCAA 2024, Paper 1 · 1 mark

Q20 · 2024 · Paper 1Unclassified1 mark

QUESTION 20

The graph shows the number of nucleotide differences observed in the cytochrome c gene of 10 species and their time since divergence.

Biology question figure

Cytochrome c genes from two new species were compared and found to have 60 nucleotide differences. Based on this information, the two species diverged approximately

(A) 48 million years ago.

(B) 60 million years ago.

(C) 72 million years ago.

(D) 120 million years ago.

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