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Genetics and heredity — Question 21

QCAA 2023, Paper 1 · 4 marks

Q21 · 2023 · Paper 1Unclassified4 marks

QUESTION 21 (4 marks)

The diagram represents a section of DNA. Identify the DNA components indicated by labels 1–4.

Biology diagram for BIO-QCAA-2023-P1-Q021
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