<prompt> On consumption of which aminoacid, requirement of methionine is reduced because of sparing effect?HomocysteineCysteineLysineArginine  <response>: Ans. is b i.e., CysteineAdequate dietary source of cysteine spares methionine. Methionine is an essential amino acid. Methionine is required for synthesis of cysteine thus cysteine is non-essential amino acid Thus, cysteine can spare the requirment of methionine in diet. 