Nitrogen Excretion

Question 1

Give step one of the Urea Cycle

Answer 1

CO2 + NH3 is turned to Carbamoyl phosphate by Carbamoyl-phosphate synthase.

Question 2

Give step two of the Urea Cycle

Answer 2

In step two of the urea cycle, Carbamoyl Phosphate is converted to Citrulline by Ornithine Transcarbamylase and Ornithine.

Question 3

Give step three of the urea cycle

Answer 3

Citrulline is converted to Argininosuccinate by Argininosuccinate synthase with L-Aspartate.

Question 4

Give step four of the urea cycle.

Answer 4

Argininosuccinate is converted to L-Arginine by Argininosuccinate Lyase.

Question 5

Give step five of the urea cycle.

Answer 5

L-Arginine is converted to L-Ornithine by Arginase, and Urea is excreted.

Question 6

What is an effect of elevated levels of NH3?

Answer 6

Lethargy or mental retardation

Question 7

What do birds and terrestrial animals convert NH3 to?

Answer 7

Uric Acid

Question 8

______ transports Ammonia from skeletal muscles to the liver.

Answer 8

Alanine

Question 9

20% of the protein found in the liver is what specific protein?

Answer 9

Carbamoyl Phosphate Synthetase I