Question

What are the inputs to one cycle of urea cycle?

(a) One molecule of CO2, one molecule of ammonia, three molecules of ATP and one molecule of aspartic acid

(b) One molecule of urea, one molecule of AMP, two molecules of ADP and one molecule of fumaric acid

(c) One molecule of aspartic acid, one molecule of ammonia, one molecule of ATP and one molecule of fumaric acid

(d) Two molecules of urea, two molecules of ammonia, one molecule of ATP and one molecule of fumaric acid

The question was asked in examination.

Enquiry is from Nitrogen Excretion and the Urea Cycle topic in division Amino Acid Oxidation and the Production of Urea of Biochemistry

Answer 1

Correct choice is (a) One molecule of CO2, one molecule of ammonia, three molecules of ATP and one molecule of aspartic acid

For explanation I would say: One molecule of CO2, one molecule of ammonia, three molecules of ATP and one molecule of aspartic acid are the inputs to one cycle of urea cycle.