Question 1

In the nitrogen cycle,one main method for ammonia entering is

Accepted Answer

A)  decomposition of organic material by invertebrates. 
B)  from the atmosphere. 
C)  through denitrification. 
D)  by leghemoglobin. 
A)  decomposition of organic material by invertebrates. 
B)  from the atmosphere. 
C)  through denitrification. 
D)  by leghemoglobin.

Question 2

Group 2 pathways can be correctly described as pathways that

Accepted Answer

A)  degrade glucogenic amino acids to generate   -ketoglutarate. 
B)  convert phenylalanine to tyrosine. 
C)  degrade alanine. 
D)  convert fumerate to oxaloacetate. 
A)  degrade glucogenic amino acids to generate   -ketoglutarate. 
B)  convert phenylalanine to tyrosine. 
C)  degrade alanine. 
D)  convert fumerate to oxaloacetate.

Question 3

Using nitrogenase to reduce N2 should require 2 ATP to be invested,but it actually takes 16 ATP.Why?

Accepted Answer

A)  It is harder to break the nitrogen triple bond than expected and requires more energy input. 
B)  Extra energy is required to produce H2. 
C)  To regenerate the MoFe protein requires the input of ATP. 
D)  To keep the nitrogenase complex associated requires an input of 4 ATP. 
A)  It is harder to break the nitrogen triple bond than expected and requires more energy input. 
B)  Extra energy is required to produce H2. 
C)  To regenerate the MoFe protein requires the input of ATP. 
D)  To keep the nitrogenase complex associated requires an input of 4 ATP.

Question 4

Explain the mechanism by which glyphosate inhibits the production of aromatic amino acids in plants.

Accepted Answer

Glyphosate is a competitive inhibitor of

Question 5

Glutamine synthetase uses ammonia to covert glutamate into

Accepted Answer

A)  glutamine. 
B)  nitrate. 
C)    -ketoglutarate. 
D)  histidine. 
A)  glutamine. 
B)  nitrate. 
C)    -ketoglutarate. 
D)  histidine.

Question 6

Both Nitrosomonas and Nitrobacter have a key role in nitrification.Nitrosomonas produces __________,whereas Nitrobacter produces __________.

Accepted Answer

A)  ammonia; nitrite 
B)  nitrite; nitrate 
C)  nitrate; nitrite 
D)  nitrite; ammonia 
A)  ammonia; nitrite 
B)  nitrite; nitrate 
C)  nitrate; nitrite 
D)  nitrite; ammonia

Question 7

How are Roundup Ready soybeans resistant to the herbicide?

Accepted Answer

Glyphosate-resistant crops were develope

Question 8

Diseases affecting heme biosynthesis as a result of deficiencies in the heme biosynthetic pathway are called

Accepted Answer

A)  porphyrias. 
B)  albinism. 
C)  shikimate. 
D)  alkaptonuria. 
A)  porphyrias. 
B)  albinism. 
C)  shikimate. 
D)  alkaptonuria.

Question 9

Using the figure below,summarize the synthesis of amino acids from oxaloacetate and pyruvate in E.coli.

Accepted Answer

Nine amino acids are synthesized from ox

Question 10

Nitrogen in biological compounds ultimately comes from what source?

Accepted Answer

A)  ammonia 
B)  nitrate 
C)  nitrogen gas 
D)  bacteria 
A)  ammonia 
B)  nitrate 
C)  nitrogen gas 
D)  bacteria

Question 11

Nitrogen balance is best described as when the daily intake of __________ equals the amount of __________ lost by excretion.

Accepted Answer

A)  ammonia; nitrogen 
B)  nitrogen; nitrogen 
C)  glucose; glucose 
D)  nitrogen; ammonia 
A)  ammonia; nitrogen 
B)  nitrogen; nitrogen 
C)  glucose; glucose 
D)  nitrogen; ammonia

Question 12

A negative nitrogen balance in a person would be an indicator of

Accepted Answer

A)  accumulation of nitrogen in the body. 
B)  a diet heavy in protein. 
C)  starvation. 
D)  overall good health. 
A)  accumulation of nitrogen in the body. 
B)  a diet heavy in protein. 
C)  starvation. 
D)  overall good health.

Question 13

If there was a loss of efficiency in the urea cycle,there would be a buildup of

Accepted Answer

A)  fumarate. 
B)  urea. 
C)  glutamine. 
D)  glucose. 
A)  fumarate. 
B)  urea. 
C)  glutamine. 
D)  glucose.

Question 14

Alanine,cysteine,glycine,and serine are all considered __________ amino acids.

Accepted Answer

A)  glucogenic 
B)  ketogenic 
C)  nonessential 
D)  urea 
A)  glucogenic 
B)  ketogenic 
C)  nonessential 
D)  urea

Question 15

The Haber process is 98% efficient.How does it achieve that level of efficiency?

Accepted Answer

A)  low temperatures and atmospheric pressure 
B)  low pressures and recycling unreacted nitrogen 
C)  high pressures and recycling nitrogen 
D)  high pressures and high concentrations of nitrogen 
A)  low temperatures and atmospheric pressure 
B)  low pressures and recycling unreacted nitrogen 
C)  high pressures and recycling nitrogen 
D)  high pressures and high concentrations of nitrogen

Question 16

Cells cannot store amino acids that accumulate as a result of protein degradation.The carbon skeletons that remain

Accepted Answer

A)  enter the urea cycle. 
B)  are used to produce new amino acids. 
C)  enter the citrate cycle. 
D)  are used to produce DNA and RNA. 
A)  enter the urea cycle. 
B)  are used to produce new amino acids. 
C)  enter the citrate cycle. 
D)  are used to produce DNA and RNA.

Question 17

Which of the following is the key regulated enzyme in urea synthesis?

Accepted Answer

A)  carbamoyl phosphate synthetase I 
B)  glutamate dehydrogenase 
C)  arginase 
D)  argininosuccinase 
A)  carbamoyl phosphate synthetase I 
B)  glutamate dehydrogenase 
C)  arginase 
D)  argininosuccinase

Question 18

In the duodenum,enteropeptidase

Accepted Answer

A)  cleaves trypsinogen to form trypsin. 
B)  cleaves chymotrypsinogen to form chymotrypsin. 
C)  generates peptides and amino acids. 
D)  neutralizes the pH of the duodenum to a pH of 7. 
A)  cleaves trypsinogen to form trypsin. 
B)  cleaves chymotrypsinogen to form chymotrypsin. 
C)  generates peptides and amino acids. 
D)  neutralizes the pH of the duodenum to a pH of 7.

Question 19

The two mechanisms to regulate protein ubiquitination are biochemical changes to

Accepted Answer

A)  target proteins and E1 ligases. 
B)  E1 and E2 ligases. 
C)  target proteins and E3 ligases. 
D)  the E2-ubiquitin-E3 complex. 
A)  target proteins and E1 ligases. 
B)  E1 and E2 ligases. 
C)  target proteins and E3 ligases. 
D)  the E2-ubiquitin-E3 complex.

Question 20

In the overall reaction of aminotransferase,how many amino acids are produced?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  0 
A)  1 
B)  2 
C)  3 
D)  0

Exam 17: Amino Acid Metabolism

In the nitrogen cycle,one main method for ammonia entering is

Group 2 pathways can be correctly described as pathways that

Using nitrogenase to reduce N2 should require 2 ATP to be invested,but it actually takes 16 ATP.Why?

Explain the mechanism by which glyphosate inhibits the production of aromatic amino acids in plants.

Glutamine synthetase uses ammonia to covert glutamate into

Both Nitrosomonas and Nitrobacter have a key role in nitrification.Nitrosomonas produces __________,whereas Nitrobacter produces __________.

How are Roundup Ready soybeans resistant to the herbicide?

Diseases affecting heme biosynthesis as a result of deficiencies in the heme biosynthetic pathway are called

Using the figure below,summarize the synthesis of amino acids from oxaloacetate and pyruvate in E.coli.

Nitrogen in biological compounds ultimately comes from what source?

Nitrogen balance is best described as when the daily intake of __________ equals the amount of __________ lost by excretion.

A negative nitrogen balance in a person would be an indicator of

If there was a loss of efficiency in the urea cycle,there would be a buildup of

Alanine,cysteine,glycine,and serine are all considered __________ amino acids.

The Haber process is 98% efficient.How does it achieve that level of efficiency?

Cells cannot store amino acids that accumulate as a result of protein degradation.The carbon skeletons that remain

Which of the following is the key regulated enzyme in urea synthesis?

In the duodenum,enteropeptidase

The two mechanisms to regulate protein ubiquitination are biochemical changes to

In the overall reaction of aminotransferase,how many amino acids are produced?

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

Using nitrogenase to reduce N₂ should require 2 ATP to be invested,but it actually takes 16 ATP.Why?

Both Nitrosomonas and Nitrobacter have a key role in nitrification.Nitrosomonas produces ,whereas Nitrobacter produces .

Nitrogen balance is best described as when the daily intake of equals the amount of lost by excretion.