Question 1

What are the four key enzymes in nitrogen fixation and assimilation in plants and bacteria?

Accepted Answer

A)  nitrogenase synthetase, glutamine complex, glutamate synthase, glutamate dehydrogenase 
B)  nitrogenase complex, glutamine synthetase, glutamate synthase, glutamate dehydrogenase 
C)  glutamine synthetase, glutamate synthase, glutamate dehydrogenase, glutamate oxidase 
D)  nitrogenase complex, glutamine synthetase, glycine synthase, glutamine dehydrogenase 
A)  nitrogenase synthetase, glutamine complex, glutamate synthase, glutamate dehydrogenase 
B)  nitrogenase complex, glutamine synthetase, glutamate synthase, glutamate dehydrogenase 
C)  glutamine synthetase, glutamate synthase, glutamate dehydrogenase, glutamate oxidase 
D)  nitrogenase complex, glutamine synthetase, glycine synthase, glutamine dehydrogenase

Question 2

When amino acids from dietary proteins enter a cell,how are they able to enter the urea cycle?

Accepted Answer

A)  through conversion to glutamine 
B)  through conversion to aspartate 
C)  by degrading down to ammonia 
D)  by getting phosphorylated 
A)  through conversion to glutamine 
B)  through conversion to aspartate 
C)  by degrading down to ammonia 
D)  by getting phosphorylated

Question 3

A no-protein diet with high doses of L-arginine helps patients with argininosuccinase deficiency because it __________ the concentration of __________.

Accepted Answer

A)  increases; fumerate that is metabolized by the citric acid cycle to lower ammonia levels 
B)  increases; ammonia in the diet to keep them regulated 
C)  increases; ornithine that is needed to maintain flux through the urea cycle 
D)  decreases; citrulline to prevent ammonia toxicity 
A)  increases; fumerate that is metabolized by the citric acid cycle to lower ammonia levels 
B)  increases; ammonia in the diet to keep them regulated 
C)  increases; ornithine that is needed to maintain flux through the urea cycle 
D)  decreases; citrulline to prevent ammonia toxicity

Question 4

A person who has alkaptonuria is easily diagnosed from his or her black urine.What causes the black color?

Accepted Answer

A)  oxidation of phenylalanine 
B)  oxidation of homogentisate 
C)  reduction of acetoacetyl-CoA 
D)  dehydration 
A)  oxidation of phenylalanine 
B)  oxidation of homogentisate 
C)  reduction of acetoacetyl-CoA 
D)  dehydration

Question 5

To increase the efficiency of the nitrogenase reaction,some plants have symbionts.The plant increases the efficiency of the reaction by providing __________,whereas bacteria provide(s)__________.

Accepted Answer

A)  fumerate and malate; additional NH3 
B)  fumerate and malate; ATP 
C)  ATP; amino acids 
D)  NADH; ATP 
A)  fumerate and malate; additional NH3 
B)  fumerate and malate; ATP 
C)  ATP; amino acids 
D)  NADH; ATP

Question 6

Using the figure below,illustrate the two final products and identify the amino group on glutamine that gets transferred.

Accepted Answer

The answer of Using the figure below,illustrate the two final...

Question 7

A person unable to produce new melanocytes is likely to have

Accepted Answer

A)  black hair. 
B)  red hair. 
C)  gray hair. 
D)  hair loss. 
A)  black hair. 
B)  red hair. 
C)  gray hair. 
D)  hair loss.

Question 8

Adenylylation of Try397 regulates glutamine synthetase by

Accepted Answer

A)  lowering activation energy. 
B)  inhibiting activity. 
C)  increasing activation energy. 
D)  increasing rate of reaction. 
A)  lowering activation energy. 
B)  inhibiting activity. 
C)  increasing activation energy. 
D)  increasing rate of reaction.

Question 9

What molecule signals the endothelial cell to produce NO?

Accepted Answer

A)  dopamine 
B)  phosphate 
C)  acetylcholine 
D)  citrulline 
A)  dopamine 
B)  phosphate 
C)  acetylcholine 
D)  citrulline

Question 10

What is the mechanism by which Roundup works?

Accepted Answer

A)  Glyphosate is a competitive inhibitor to plant EPSP synthase. 
B)  Urea is a competitive inhibitor to plant chorismate synthase. 
C)  Glyphosate is an activator to plant EPSP synthase. 
D)  Anthranilate is an activator to chorismate synthase. 
A)  Glyphosate is a competitive inhibitor to plant EPSP synthase. 
B)  Urea is a competitive inhibitor to plant chorismate synthase. 
C)  Glyphosate is an activator to plant EPSP synthase. 
D)  Anthranilate is an activator to chorismate synthase.

Question 11

Classify the 20 amino acids as glucogenic,ketogenic,or both.

Accepted Answer

The answer of Classify the 20 amino acids as glucogenic,ketogenic,or...

Question 12

What purpose does nitrogen fixation and assimilation serve in the biosphere?

Accepted Answer

Nitrogen fixation takes place in bacteri

Question 13

Which metabolic process is the cause of albinism?

Accepted Answer

A)  inefficient production of dopamine 
B)  the enzyme tyrosinase working inefficiently 
C)  overproduction of NADPH 
D)  low levels of ATP available in the cell 
A)  inefficient production of dopamine 
B)  the enzyme tyrosinase working inefficiently 
C)  overproduction of NADPH 
D)  low levels of ATP available in the cell

Question 14

Eukaryotic proteasome selectively degrade which type of proteins?

Accepted Answer

A)  all proteins; they are not selective 
B)  ubiquitinated proteins 
C)  phosphorylated proteins 
D)  ATP-dependent proteins 
A)  all proteins; they are not selective 
B)  ubiquitinated proteins 
C)  phosphorylated proteins 
D)  ATP-dependent proteins

Question 15

Because nitrogenase is inhibited by oxygen,under what conditions can the enzyme operate to reduce N2?

Accepted Answer

A)  aerobic conditions 
B)  anaerobic conditions 
C)  high pressure 
D)  high temperature 
A)  aerobic conditions 
B)  anaerobic conditions 
C)  high pressure 
D)  high temperature

Question 16

The carbon skeletons of all 20 amino acids side chains are derived from just seven metabolic intermediates and their associated pathways.What are those intermediates and pathways?

Accepted Answer

Three glycolytic pathway intermediates:

Question 17

A person who has phenylketonuria will have a buildup of which molecule in the cell?

Accepted Answer

A)  tyrosine 
B)  phenylalanine 
C)  pyruvate 
D)  alanine 
A)  tyrosine 
B)  phenylalanine 
C)  pyruvate 
D)  alanine

Question 18

Which of the following is the net reaction of the urea cycle?

Accepted Answer

A)  Urea + Fumerate + 2 ADP + 2Pi + AMP + PPi  NH+ + HCO3- + aspartate + 3ATP 
B)    
C)   
D)  NH+ HCO3     + aspartate + 2 ADP + 2Pi + AMP + PPi  Urea + fumerate + 3ATP 
A)  Urea + Fumerate + 2 ADP + 2Pi + AMP + PPi  NH+ + HCO3- + aspartate + 3ATP 
B)    
C)   
D)  NH+ HCO3     + aspartate + 2 ADP + 2Pi + AMP + PPi  Urea + fumerate + 3ATP

Question 19

How does biological fixation convert nitrogen to ammonia?

Accepted Answer

A)  by reducing nitrogen 
B)  by combining nitrogen with carbon 
C)  through the ATP-dependent process catalyzed by nitrogenase complex 
D)  through the NADH-dependent process catalyzed by glutamate dehydrogenase 
A)  by reducing nitrogen 
B)  by combining nitrogen with carbon 
C)  through the ATP-dependent process catalyzed by nitrogenase complex 
D)  through the NADH-dependent process catalyzed by glutamate dehydrogenase

Question 20

Summarize the synthesis of the catecholamines.

Accepted Answer

Tyrosine is the metabolons precursor to

Exam 17: Amino Acid Metabolism

What are the four key enzymes in nitrogen fixation and assimilation in plants and bacteria?

When amino acids from dietary proteins enter a cell,how are they able to enter the urea cycle?

A no-protein diet with high doses of L-arginine helps patients with argininosuccinase deficiency because it __________ the concentration of __________.

A person who has alkaptonuria is easily diagnosed from his or her black urine.What causes the black color?

To increase the efficiency of the nitrogenase reaction,some plants have symbionts.The plant increases the efficiency of the reaction by providing __________,whereas bacteria provide(s)__________.

Using the figure below,illustrate the two final products and identify the amino group on glutamine that gets transferred.

A person unable to produce new melanocytes is likely to have

Adenylylation of Try397 regulates glutamine synthetase by

What molecule signals the endothelial cell to produce NO?

What is the mechanism by which Roundup works?

Classify the 20 amino acids as glucogenic,ketogenic,or both.

What purpose does nitrogen fixation and assimilation serve in the biosphere?

Which metabolic process is the cause of albinism?

Eukaryotic proteasome selectively degrade which type of proteins?

Because nitrogenase is inhibited by oxygen,under what conditions can the enzyme operate to reduce N2?

The carbon skeletons of all 20 amino acids side chains are derived from just seven metabolic intermediates and their associated pathways.What are those intermediates and pathways?

A person who has phenylketonuria will have a buildup of which molecule in the cell?

Which of the following is the net reaction of the urea cycle?

How does biological fixation convert nitrogen to ammonia?

Summarize the synthesis of the catecholamines.

Principles of Biochemistry

Physical Biochemistry: Energy Conversion,water,and Membranes

Nucleic Acid Structure and Function

Protein Structure

Methods in Protein Biochemistry

Protein Function

Enzyme Mechanisms

Cell Signaling Systems

Glycolysis: a Paradigm of Metabolic Regulation

The Citrate Cycle

Oxidative Phosphorylation

Photosynthesis

Carbohydrate Structure and Function

Carbohydrate Metabolism

Lipid Structure and Function

Lipid Metabolism

Nucleotide Metabolism

Metabolic Integration

Dna Replication, repair, and Recombination

Rna Synthesis, processing, and Gene Silencing

Protein Synthesis, posttranslational Modification, and Transport

Gene Regulation

Filters

A no-protein diet with high doses of L-arginine helps patients with argininosuccinase deficiency because it the concentration of .

To increase the efficiency of the nitrogenase reaction,some plants have symbionts.The plant increases the efficiency of the reaction by providing ,whereas bacteria provide(s).

Because nitrogenase is inhibited by oxygen,under what conditions can the enzyme operate to reduce N₂?