A deep-sea diver surfaces rapidly after prolonged exposure to high pressure. Which effect on collagen synthesis is likely if the diver also has a vitamin C deficiency?

💡 Explanation

Vitamin C is a crucial cofactor for prolyl hydroxylase, the enzyme that hydroxylates proline residues in collagen. Without adequate hydroxylation, collagen fibrils cannot properly cross-link, forming weak and unstable structures; because of this impaired hydroxylation, the tensile strength of collagen is significantly reduced. Therefore, option D is correct, rather than the other options which describe normal or enhanced collagen synthesis.

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