chapter 19

Question 1

1-The carbon atom source while producing urea in the urea cycle is?

1-None 
2-CO2 
3-Glucose 
4-Aspartic acid 
5-Arginine

Question 2

2-Urea production occurs almost exclusively in ?

1-Liver 
2-None 
3-Urine 
4-Kidneys 
5-Blood

Answer 2

1-Liver

Question 3

3-The first enzyme in the pathway carbamoyl phosphate synthase 1 , is allosterically activated by ?

1-Acetyl COA 
2-None 
3-Carbamoyl phosphate 
4-N - acetylglutamate 
5-Glutamate

Answer 3

4-N - acetylglutamate

Question 4

4-Which of the following is the first amino group entering into urea cycle ?

1-Citrulline 
2-Argininosuccinate 
3-Ornithine 
4-None 
5-Carbamoyl phosphate

Question 5

5-What are the products of urea cycle ?

1-None

2-Two molecres of urea , two molecules of ammonia , one molecule of ATP and one molecule of fumaric acid.

3-One molecule of aspartic acid , one molecue of ammonia one molecule of ATP and one molecule of fumaric acid.

4-one molecule of urea ,one molecule of AMP , two molecules of ADP and one molecule of fumaric acid .

5-One molecule of urea , one molecule of ammonia one molecule of ATP and one molecule of fumaric acid.

Answer 5

4-one molecule of urea ,one molecule of AMP , two molecules of ADP and one molecule of fumaric acid .

Question 6

6-Which of the following operates at an important intersection of carbon and nitrogen metabolism?

1-Glutamine synthase 
2-Glutaminase 
3-Glutamate dehydrogenase 
4-None 
5-Amino transferases

Question 7

………has a direct neurotoxic effect on the CNS

Answer 7

ammonia

Question 8

symptoms of …………………, which include tremors, slurring of speech, somnolence (drowsiness), vomiting, cerebral edema, and blurring of vision

Answer 8

ammonia intoxication,hyperammonemia

Question 9

………….is a common cause of acquired hyperammonemia

Answer 9

liver

Question 10

the synthesis of urea is?

a-irreversible
b-reversible

Answer 10

a-irreversible

Question 11

A portion of the urea diffuses from the blood into the intestine
and is cleaved to CO2 and ammonia by ?

Answer 11

bacterial urease

Question 12

……….. which is used as a source of nitrogen in the urea cycle

Answer 12

aspartate

Question 13

Which of the following operates of an important intersection of carbon and nitrogen metabolism ?
Glutamine synthetase 
Glutaminase 
Glutamate dehydrogenase 
None 
Amino transferases

Answer 13

Glutamate dehydrogenase