Question 1

Identify a pathway in which glucose is synthesized in the body from the intermediates of the glycolytic and citric acid pathways.

Accepted Answer

A)  glycolysis 
B)  the Calvin cycle 
C)  gluconeogenesis 
D)  the Cori cycle 
A)  glycolysis 
B)  the Calvin cycle 
C)  gluconeogenesis 
D)  the Cori cycle

Question 2

Which of the following amino acids cannot be synthesized from glutamate?

Accepted Answer

A)  alanine 
B)  asparagine 
C)  serine 
D)  tyrosine 
A)  alanine 
B)  asparagine 
C)  serine 
D)  tyrosine

Question 3

Which of the following coenzymes is required for the synthesis of glutamate from α-ketoglutarate?

Accepted Answer

A)  FAD 
B)  FADH2 
C)  NADH 
D)  NAD+ 
A)  FAD 
B)  FADH2 
C)  NADH 
D)  NAD+

Question 4

Which of the following products is formed when a glycerol-1-phosphate molecule reacts with two molecules of acyl CoA?

Accepted Answer

A)  a choline molecule 
B)  a citrate molecule 
C)  a phosphatidate molecule 
D)  a triphosphate molecule 
A)  a choline molecule 
B)  a citrate molecule 
C)  a phosphatidate molecule 
D)  a triphosphate molecule

Question 5

The cellular concentration of which compound determines the fate of fats?

Accepted Answer

A)  malonyl-CoA 
B)  acetyl-CoA 
C)  succinyl CoA 
D)  acyl CoA 
A)  malonyl-CoA 
B)  acetyl-CoA 
C)  succinyl CoA 
D)  acyl CoA

Question 6

Consider the following reaction sequence.   Which statement is true of the product formed in the second step of the given reaction sequence?

Accepted Answer

A)  It is called glycogen. 
B)  It is an example of a polysaccharide. 
C)  It can have from 30,000 to 120,000 molecules of glucose. 
D)  All of these statements are true. 
A)  It is called glycogen. 
B)  It is an example of a polysaccharide. 
C)  It can have from 30,000 to 120,000 molecules of glucose. 
D)  All of these statements are true.

Question 7

Which of the following molecules is the source of carbon during fatty acid synthesis?

Accepted Answer

A)  acetate 
B)  acetyl-CoA 
C)  malate 
D)  succinyl CoA 
A)  acetate 
B)  acetyl-CoA 
C)  malate 
D)  succinyl CoA

Question 8

In which organ does the Cori cycle take place?

Accepted Answer

A)  the intestine 
B)  the liver 
C)  the muscles 
D)  the spleen 
A)  the intestine 
B)  the liver 
C)  the muscles 
D)  the spleen

Question 9

Identify a reactant in the light reactions of photosynthesis.

Accepted Answer

A)  carbon dioxide 
B)  water 
C)  both carbon dioxide and water 
D)  neither carbon dioxide nor water 
A)  carbon dioxide 
B)  water 
C)  both carbon dioxide and water 
D)  neither carbon dioxide nor water

Question 10

Consider the following reaction sequence.   Which of the following statements is true of this reaction sequence?

Accepted Answer

A)  It is a step in a process called glycogenesis. 
B)  It occurs within the mitochondrial matrix. 
C)  It can also occur in the absence of nucleotides. 
D)  All of these statements are true. 
A)  It is a step in a process called glycogenesis. 
B)  It occurs within the mitochondrial matrix. 
C)  It can also occur in the absence of nucleotides. 
D)  All of these statements are true.

Question 11

Which of the following statements is true of farnesyl pyrophosphate and geranyl pyrophosphate?

Accepted Answer

A)  They are the precursors of cholesterol biosynthesis. 
B)  They are intermediates in cholesterol biosynthesis. 
C)  They are structural isomers of each other. 
D)  None of these statements is correct. 
A)  They are the precursors of cholesterol biosynthesis. 
B)  They are intermediates in cholesterol biosynthesis. 
C)  They are structural isomers of each other. 
D)  None of these statements is correct.

Question 12

Identify a product of the dark reactions of photosynthesis.

Accepted Answer

A)  glucose 
B)  molecular oxygen 
C)  both glucose and molecular oxygen 
D)  neither glucose nor molecular oxygen 
A)  glucose 
B)  molecular oxygen 
C)  both glucose and molecular oxygen 
D)  neither glucose nor molecular oxygen

Question 13

How will the body respond if a normal biosynthetic pathway is blocked?

Accepted Answer

A)  The body will develop a different and completely new pathway to replace the blocked pathway. 
B)  The body will not be able to produce the compounds of the blocked pathway and will eventually die. 
C)  The body will use the reverse of the degradation pathway to make the necessary compounds. 
D)  The body will not be affected by the blockage of a biosynthetic pathway. 
A)  The body will develop a different and completely new pathway to replace the blocked pathway. 
B)  The body will not be able to produce the compounds of the blocked pathway and will eventually die. 
C)  The body will use the reverse of the degradation pathway to make the necessary compounds. 
D)  The body will not be affected by the blockage of a biosynthetic pathway.

Question 14

Examine the following chemical reaction.   Which of the following statements is true of this reaction?

Accepted Answer

A)  Alanine is one of the products of the given reaction. 
B)  This reaction is an example of a deamination reaction. 
C)  The product of this reaction is an essential amino acid. 
D)  All of these statements are true. 
A)  Alanine is one of the products of the given reaction. 
B)  This reaction is an example of a deamination reaction. 
C)  The product of this reaction is an essential amino acid. 
D)  All of these statements are true.

Question 15

Which of the following metabolic cycles utilizes lactate as the starting material for gluconeogenesis?

Accepted Answer

A)  the Calvin cycle 
B)  the citric acid cycle 
C)  the Cori cycle 
D)  the Krebs cycle 
A)  the Calvin cycle 
B)  the citric acid cycle 
C)  the Cori cycle 
D)  the Krebs cycle

Question 16

How does the presence of excess inorganic phosphate affect phosphorylase-catalyzed glycogen synthesis?

Accepted Answer

A)  It favors the hydrolysis of glycogen and the production of glucose-1-phosphate. 
B)  It prevents the hydrolysis of glycogen and increases cross-linking in glycogen. 
C)  It enhances the rate of glycogen synthesis. 
D)  It enhances the rate of glycogen breakdown. 
A)  It favors the hydrolysis of glycogen and the production of glucose-1-phosphate. 
B)  It prevents the hydrolysis of glycogen and increases cross-linking in glycogen. 
C)  It enhances the rate of glycogen synthesis. 
D)  It enhances the rate of glycogen breakdown.

Question 17

How does prenylation affect a protein?

Accepted Answer

A)  It makes a protein more hydrophilic. 
B)  It makes a protein more hydrophobic. 
C)  It causes a protein to become fixed in the lipid bilayer of a membrane. 
D)  It prevents a protein from participating in signal transduction. 
A)  It makes a protein more hydrophilic. 
B)  It makes a protein more hydrophobic. 
C)  It causes a protein to become fixed in the lipid bilayer of a membrane. 
D)  It prevents a protein from participating in signal transduction.

Question 18

Why are dietary cholesterol and cholesterol synthesized in the liver not available for forming synapses?

Accepted Answer

A)  They are consumed by various parts of the body before they reach the brain. 
B)  They cannot cross the blood-brain barrier because they are present as LDL. 
C)  Both of these statements are valid reasons. 
D)  Neither of these statements is a valid reason. 
A)  They are consumed by various parts of the body before they reach the brain. 
B)  They cannot cross the blood-brain barrier because they are present as LDL. 
C)  Both of these statements are valid reasons. 
D)  Neither of these statements is a valid reason.

Question 19

Of the 20 amino acids that are found in human proteins, how many are essential amino acids?

Accepted Answer

A)  5 
B)  10 
C)  15 
D)  20 
A)  5 
B)  10 
C)  15 
D)  20

Question 20

Which of the following chemical bonds is present in acetyl-ACP?

Accepted Answer

A)  a disulfide bond 
B)  a thioether bond 
C)  a thioester bond 
D)  a thiol bond 
A)  a disulfide bond 
B)  a thioether bond 
C)  a thioester bond 
D)  a thiol bond

Exam 28: Biosynthetic Pathways

Identify a pathway in which glucose is synthesized in the body from the intermediates of the glycolytic and citric acid pathways.

Which of the following amino acids cannot be synthesized from glutamate?

Which of the following coenzymes is required for the synthesis of glutamate from α-ketoglutarate?

Which of the following products is formed when a glycerol-1-phosphate molecule reacts with two molecules of acyl CoA?

The cellular concentration of which compound determines the fate of fats?

Consider the following reaction sequence. Which statement is true of the product formed in the second step of the given reaction sequence?

Which of the following molecules is the source of carbon during fatty acid synthesis?

In which organ does the Cori cycle take place?

Identify a reactant in the light reactions of photosynthesis.

Consider the following reaction sequence. Which of the following statements is true of this reaction sequence?

Which of the following statements is true of farnesyl pyrophosphate and geranyl pyrophosphate?

Identify a product of the dark reactions of photosynthesis.

How will the body respond if a normal biosynthetic pathway is blocked?

Examine the following chemical reaction. Which of the following statements is true of this reaction?

Which of the following metabolic cycles utilizes lactate as the starting material for gluconeogenesis?

How does the presence of excess inorganic phosphate affect phosphorylase-catalyzed glycogen synthesis?

How does prenylation affect a protein?

Why are dietary cholesterol and cholesterol synthesized in the liver not available for forming synapses?

Of the 20 amino acids that are found in human proteins, how many are essential amino acids?

Which of the following chemical bonds is present in acetyl-ACP?

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