Urea Cycle

Question 1

Give step one of the Urea cycle

Answer 1

CO2 + NH3 is converted to Carbamoyl phosphate by Carbamoyl phosphate synthase. This consumes 2ATP to form ADP + Pi.

Question 2

Give step two of the urea cycle

Answer 2

Carbamoyl phosphate is converted to Citrulline by Ornithine Carbamoyl transferase. One phosphate is released.

Question 3

Give step three of the urea cycle

Answer 3

Citrulline is combined with L-Aspartate to to form Argininosuccinate by Argininosuccinate synthase. One ATP is consumed to form AMP and PPi.

Question 4

Give step four of the Urea cycle

Answer 4

Argininosuccinate is converted to L-Arginine by Argininosuccinate lyase, and fumrate is released.

Question 5

Give step five (last) of the urea cycle.

Answer 5

L-Arginine is converted to L-Ornithine by Arginase. A water molecule is consumed and Urea released.