Collagen synthesis: scurvy: practice question

A Biochemistry question in the style of the NEET PG paper. Answer it first, then read why the right option is right and why each of the others is wrong.

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Biochemistry · Collagen synthesis: scurvy

Sample item

Poor wound healing and perifollicular haemorrhages in scurvy arise because vitamin C is needed for hydroxylation of which residues in collagen?

Original practice item, not a recalled exam question. Nothing here is recorded.

The answer and the reasoning

D. Proline and lysine

Ascorbate supports prolyl and lysyl hydroxylases in the rough endoplasmic reticulum. Hydroxylation stabilises collagen triple helices and permits normal cross-linking.

Option by option

  • A. Tryptophan and tyrosine

    These aromatic residues are unrelated to scurvy's collagen defect.

  • B. Serine and threonine

    These residues are not the classic collagen hydroxylation sites.

  • C. Glycine and alanine

    Glycine is abundant in collagen but is not the vitamin C-dependent hydroxylation target.

  • D. Proline and lysine (correct)

    Correct. Proline and lysine hydroxylation is vitamin C dependent.

Source note: Original NextPrep sample item — pending expert review. This item is original practice material awaiting independent expert review, so confirm important facts in a standard textbook.

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Questions about this Biochemistry question

What is the answer to this Biochemistry question?

The best answer is D, Proline and lysine. Ascorbate supports prolyl and lysyl hydroxylases in the rough endoplasmic reticulum.

Why is "Tryptophan and tyrosine" not the answer?

These aromatic residues are unrelated to scurvy's collagen defect.

Why is "Serine and threonine" not the answer?

These residues are not the classic collagen hydroxylation sites.

Why is "Glycine and alanine" not the answer?

Glycine is abundant in collagen but is not the vitamin C-dependent hydroxylation target.

What concept does this question test?

It tests Collagen synthesis: scurvy in Biochemistry. Hydroxylation stabilises collagen triple helices and permits normal cross-linking.

How hard is this question?

We tag it as an application question: it asks you to use a fact on a patient or a finding. The tag is our own editorial judgement, not an official difficulty rating, so read the reason for every option, not only the answer.

How should I study Collagen synthesis: scurvy?

Build one table of enzyme deficiency, disease, inheritance and key finding, then revise it by spaced recall. Then use the flashcards and the other Biochemistry questions on this site to test what stuck.

Is this a real NEET PG question?

No. It is an original practice item (editorial status: sample, version 1). NextPrep does not publish recalled or leaked questions, and independent faculty review of this item has not been completed yet, so confirm important facts in a standard textbook.