Amino acids: 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.

Try it

Biochemistry · Amino acids

Sample item

Which amino acid is precursor of serotonin?

AGlycineBTryptophanCValineDTyrosine

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

The answer and the reasoning

B. Tryptophan

This item reviews Amino acids; Tryptophan is the best answer because it directly matches the biochemical or pathological mechanism described.

Option by option

A. Glycine
Glycine is plausible but not the best answer.
B. Tryptophan (correct)
Correct. Tryptophan fits the defining mechanism.
C. Valine
Valine is unsupported by the key feature.
D. Tyrosine
Tyrosine does not fit the stated pattern.

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.

Questions about this Biochemistry question

What is the answer to this Biochemistry question?

The best answer is B, Tryptophan. This item reviews Amino acids; Tryptophan is the best answer because it directly matches the biochemical or pathological mechanism described.

Why is "Glycine" not the answer?

Glycine is plausible but not the best answer.

Why is "Valine" not the answer?

Valine is unsupported by the key feature.

Why is "Tyrosine" not the answer?

Tyrosine does not fit the stated pattern.

What concept does this question test?

It tests Amino acids in Biochemistry. The correct option holds because: Correct. Tryptophan fits the defining mechanism.

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 Amino acids?

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.