Amino acid metabolism: practice question

The best answer is A, Pyrimidine ring. Glycine contributes C4, C5 and N7 of the purine ring, is condensed with succinyl-CoA to form delta-aminolevulinic acid for haem, and forms part of creatine and glutathione.

Creatine is formed from glycine, arginine and methionine.

Haem synthesis starts with glycine condensing with succinyl-CoA.

Glycine donates three atoms to the purine ring.

It tests Amino acid metabolism in Biochemistry. The pyrimidine ring is built instead from aspartate and carbamoyl phosphate from glutamine.

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.

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.

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.