BIOCHEM 38

Question 1

carbamoyl phosphate is formed by

Answer 1

clevage of 2 ATP, NH4+, bicarb

catalyzed by CPSI

Question 2

Citrulline is formed by

Answer 2

Carbamoyl phosphate rxn w ornithine

catalyzed by OTC

Question 3

mitochondrial citrulline is exchanged for

Answer 3

cytoplasmic ornithine

Question 4

When argininosuccinate is cleaved by Argininosuccinate what 2 products are formed?

Answer 4

fumarate and arginine

Question 5

Where does citrullin conversion to arginine which is then cleaved to urea take place?

Answer 5

cytosol

Question 6

What 3 enzymes can fix ammonia directly into organic molecules?

Answer 6

1. Glutamine synthetase
2. Glutamate dehydrogenase
3. carbamoyl phosphate synthetase

Question 7

What is the major regulatory enzyme of the urea cycle?

Answer 7

CPSI

Question 8

CPSI is regulated by what compound? and how?

Answer 8

N-acetyleglutamate -allosterically

Question 9

N-acetylglutamate synthesis is stimulated by what AA?

Answer 9

Arginine

Question 10

Histine –>

Answer 10

deamination –> urocante

Question 11

Serine –>

Answer 11

pyruvate

Question 12

theronine –>

Answer 12

a-ketobutyrate

Question 13

asparagine –>

Answer 13

deaminated by asparaginase –> asparatate

Question 14

Glutaminate –>

Answer 14

by glutaminase –> Glutamate