What enzyme is deficient in Lesch-Nyhan syndrome?
Adenine phosphoribosyltransferase (APRT)
Uridine phosphorylase
Uridine kinase
Hypoxanthine-guanine phosphoribosyltransferase (HGPRT)
The urea cycle is vital to the excretion of ammonia, a harmful byproduct of amino acid breakdown.
What enzyme in the urea cycle converts L-ornithine to L-citrulline?
Argininosuccinate synthetase
Ornithine transcarbamylase
Ornithine synthetase
Argininosuccinate lyase
