Question 1

Use the following to answer questions 
Choose the correct answer from the list below. Not all of the answers will be used.
-Serine and threonine are deaminated by the enzyme _______________.

Accepted Answer

A)  hyperammonemia
B)  aminotransferases
C)  methionine
D)  S-adenosylmethionine
E)  glutamate dehydrogenaseF) oxaloacetateG) biopterinH) glutamateI) hippurateJ) ureaK) dehydrataseL) dioxygenasesM) ammonia disorder

Question 2

Which of the following is an allosteric activator of mammalian carbamoyl phosphate synthetase?

Accepted Answer

A)   α-ketoglutarate
B)   N-acetylaspartate
C)   N-acetylglutamate
D)   glutamine
E)   None of the above.

Question 3

Write the net equation of the urea cycle and indicate whether energy is produced or consumed by the cycle.

Accepted Answer

CO2 + NH4+ + 3 ATP + Asp + 2 H...

Question 4

Use the following to answer questions 
Choose the correct answer from the list below. Not all of the answers will be used.
-The methyl group donor _______________ is the product of the first step of methionine degradation.

Accepted Answer

A)  hyperammonemia
B)  aminotransferases
C)  methionine
D)  S-adenosylmethionine
E)  glutamate dehydrogenaseF) oxaloacetateG) biopterinH) glutamateI) hippurateJ) ureaK) dehydrataseL) dioxygenasesM) ammonia disorder

Question 5

Use the following to answer questions 
Choose the correct answer from the list below. Not all of the answers will be used.
-The molecule _______________ is formed from excess NH4+ by ureotelic organisms.

Accepted Answer

A)  hyperammonemia
B)  aminotransferases
C)  methionine
D)  S-adenosylmethionine
E)  glutamate dehydrogenaseF) oxaloacetateG) biopterinH) glutamateI) hippurateJ) ureaK) dehydrataseL) dioxygenasesM) ammonia disorder

Question 6

Which amino acids can be converted to pyruvate by a single enzyme-catalyzed reaction?

Accepted Answer

Alanine can be converted to py...

Question 7

Oxidative deamination of glutamate results in free ammonium ions and ___________________.

Accepted Answer

The answer of Oxidative deamination of glutamate results in free...

Question 8

Why are more uricotelic organisms found in the desert than in the tropics?

Accepted Answer

Uricotelic organisms remove to...

Question 9

Which of the following amino acids is/are glucogenic?

Accepted Answer

A)   asparagine
B)   methionine
C)   valine
D)   lysine
E)   A, B, and C

Question 10

The genetic deficiency of the enzyme ___________________ results in a condition referred to as phenylketonuria.

Accepted Answer

phenylalan...

Question 11

How is the urea cycle linked to the citric acid cycle?

Accepted Answer

During the urea cycle, aspartate brings in the second nitrogen by combining with citrulline to form argininosuccinate. Then argininosuccinate is cleaved, forming arginine and fumarate. The fumarate is then converted into malate and then oxidized to oxaloacetate, which can be transaminated to aspartate or serve as a precursor to glucose. Fumarate, malate, and oxaloacetate are all intermediates of the citric acid cycle. Figure 30.3 in the text shows this integration.

Question 12

In the urea cycle, the second nitrogen of urea enters the cycle in the form of which of the following metabolites?

Accepted Answer

A)   alanine
B)   glutamine
C)   ornithine
D)   aspartate
E)   arginine

Question 13

Use the following to answer questions 
Choose the correct answer from the list below. Not all of the answers will be used.
-The molecule _______________ is oxidatively deaminated to an ammonium ion.

Accepted Answer

A)  hyperammonemia
B)  aminotransferases
C)  methionine
D)  S-adenosylmethionine
E)  glutamate dehydrogenaseF) oxaloacetateG) biopterinH) glutamateI) hippurateJ) ureaK) dehydrataseL) dioxygenasesM) ammonia disorder H

Question 14

What is the cause of PKU? Give the structure of the abnormal metabolite that accumulates from which this condition gets its name.

Accepted Answer

PKU is the abbreviation for phenylketonu...

Question 15

Which of the following amino acids is/are ketogenic?

Accepted Answer

A)   asparagine
B)   methionine
C)   valine
D)   lysine
E)   A, B, and C

Question 16

Describe the glucose-alanine cycle and its significance in amino acid metabolism.

Accepted Answer

During prolonged exercise and fasting, muscles use branched-chain amino acids as fuel. This degradation takes place in the muscle, but conversion to urea is not possible in this tissue, thus transport to the liver is required. The amino nitrogen is removed by transamination to produce glutamate. The glutamate then transaminates with pyruvate, producing alanine, which is released into the blood and transported to the liver. In the liver, the alanine is converted to pyruvate and the urea is metabolized to urea. The pyruvate is converted to glucose by gluconeogenesis and the glucose is transported back to the muscle via the bloodstream.

Question 17

Use the following to answer questions 
Choose the correct answer from the list below. Not all of the answers will be used.
-The _______________ enzyme catalyzes an oxidative deamination and can utilize either NAD+ or NADP+.

Accepted Answer

A)  hyperammonemia
B)  aminotransferases
C)  methionine
D)  S-adenosylmethionine
E)  glutamate dehydrogenaseF) oxaloacetateG) biopterinH) glutamateI) hippurateJ) ureaK) dehydrataseL) dioxygenasesM) ammonia disorder

Question 18

Surplus amino acids are:

Accepted Answer

A)   stored in proteasomes.
B)   stored in protein scaffolds.
C)   used as metabolic fuel.
D)   All of the above.
E)   None of the above.

Question 19

Ammoniotelic organisms excrete excess nitrogen as:

Accepted Answer

A)   N2H8.
B)   NH4+.
C)   urea.
D)   All of the above.
E)   None of the above.

Question 20

Which amino acid(s)  is/are converted to tyrosine in the degradative pathway?

Accepted Answer

A)   phenylalanine
B)   tryptophan
C)   methionine
D)   A and B
E)   A, B, and C

Exam 30: Amino Acid Degradation and the Urea Cycle

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -Serine and threonine are deaminated by the enzyme _______________.

Correct Answer
verified

Which of the following is an allosteric activator of mammalian carbamoyl phosphate synthetase?

Correct Answer
verified

Write the net equation of the urea cycle and indicate whether energy is produced or consumed by the cycle.

Correct Answer
verified
CO2 + NH4+ + 3 ATP + Asp + 2 H...
View Answer

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -The methyl group donor _______________ is the product of the first step of methionine degradation.

Correct Answer
verified

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -The molecule _______________ is formed from excess NH4+ by ureotelic organisms.

Correct Answer
verified

Which amino acids can be converted to pyruvate by a single enzyme-catalyzed reaction?

Correct Answer
verified
Alanine can be converted to py...
View Answer

Oxidative deamination of glutamate results in free ammonium ions and ___________________.

Correct Answer
verified

Why are more uricotelic organisms found in the desert than in the tropics?

Correct Answer
verified
Uricotelic organisms remove to...
View Answer

Which of the following amino acids is/are glucogenic?

Correct Answer
verified

The genetic deficiency of the enzyme ___________________ results in a condition referred to as phenylketonuria.

Correct Answer
verified
phenylalan...
View Answer

How is the urea cycle linked to the citric acid cycle?

In the urea cycle, the second nitrogen of urea enters the cycle in the form of which of the following metabolites?

Correct Answer
verified

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -The molecule _______________ is oxidatively deaminated to an ammonium ion.

Correct Answer
verified
H

What is the cause of PKU? Give the structure of the abnormal metabolite that accumulates from which this condition gets its name.

Correct Answer
verified
PKU is the abbreviation for phenylketonu...
View Answer

Which of the following amino acids is/are ketogenic?

Correct Answer
verified

Describe the glucose-alanine cycle and its significance in amino acid metabolism.

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -The _______________ enzyme catalyzes an oxidative deamination and can utilize either NAD+ or NADP+.

Correct Answer
verified

Surplus amino acids are:

Correct Answer
verified

Ammoniotelic organisms excrete excess nitrogen as:

Correct Answer
verified

Which amino acid(s) is/are converted to tyrosine in the degradative pathway?

Correct Answer
verified

Exam 30: Amino Acid Degradation and the Urea Cycle

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -Serine and threonine are deaminated by the enzyme _______________.

Correct AnswerverifiedShow Answer

Which of the following is an allosteric activator of mammalian carbamoyl phosphate synthetase?

Correct AnswerverifiedShow Answer

Write the net equation of the urea cycle and indicate whether energy is produced or consumed by the cycle.

Correct AnswerverifiedCO2 + NH4+ + 3 ATP + Asp + 2 H...View AnswerShow Answer

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -The methyl group donor _______________ is the product of the first step of methionine degradation.

Correct AnswerverifiedShow Answer

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -The molecule _______________ is formed from excess NH4+ by ureotelic organisms.

Correct AnswerverifiedShow Answer

Which amino acids can be converted to pyruvate by a single enzyme-catalyzed reaction?

Correct AnswerverifiedAlanine can be converted to py...View AnswerShow Answer

Oxidative deamination of glutamate results in free ammonium ions and ___________________.

Correct AnswerverifiedShow Answer

Why are more uricotelic organisms found in the desert than in the tropics?

Correct AnswerverifiedUricotelic organisms remove to...View AnswerShow Answer

Which of the following amino acids is/are glucogenic?

Correct AnswerverifiedShow Answer

The genetic deficiency of the enzyme ___________________ results in a condition referred to as phenylketonuria.

Correct Answerverifiedphenylalan...View AnswerShow Answer

How is the urea cycle linked to the citric acid cycle?

In the urea cycle, the second nitrogen of urea enters the cycle in the form of which of the following metabolites?

Correct AnswerverifiedShow Answer

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -The molecule _______________ is oxidatively deaminated to an ammonium ion.

Correct AnswerverifiedH

What is the cause of PKU? Give the structure of the abnormal metabolite that accumulates from which this condition gets its name.

Correct AnswerverifiedPKU is the abbreviation for phenylketonu...View AnswerShow Answer

Which of the following amino acids is/are ketogenic?

Correct AnswerverifiedShow Answer

Describe the glucose-alanine cycle and its significance in amino acid metabolism.

Use the following to answer questions Choose the correct answer from the list below. Not all of the answers will be used. -The _______________ enzyme catalyzes an oxidative deamination and can utilize either NAD+ or NADP+.

Correct AnswerverifiedShow Answer

Surplus amino acids are:

Correct AnswerverifiedShow Answer

Ammoniotelic organisms excrete excess nitrogen as:

Correct AnswerverifiedShow Answer

Which amino acid(s) is/are converted to tyrosine in the degradative pathway?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
CO2 + NH4+ + 3 ATP + Asp + 2 H...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
Alanine can be converted to py...
View Answer

Correct Answer
verified

Correct Answer
verified
Uricotelic organisms remove to...
View Answer

Correct Answer
verified

Correct Answer
verified
phenylalan...
View Answer

Correct Answer
verified

Correct Answer
verified
H

Correct Answer
verified
PKU is the abbreviation for phenylketonu...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified