Question 1

Fermentation is the aerobic conversion of glucose to ethanol and CO2.

Accepted Answer

A) True 
 B)False  False

Question 2

Which process requires the coenzyme NADH?

Accepted Answer

A) glucose $\rightarrow$ pyruvate 
B) pyruvate $\rightarrow$ acetaldehyde 
C) pyruvate $\rightarrow$ lactate 
D) pyruvate $\rightarrow$ acetyl CoA 
E) More than one of the processes above requires the coenzyme NADH. 
A) glucose $\rightarrow$ pyruvate 
B) pyruvate $\rightarrow$ acetaldehyde 
C) pyruvate $\rightarrow$ lactate 
D) pyruvate $\rightarrow$ acetyl CoA 
E) More than one of the processes above requires the coenzyme NADH. C

Question 3

A glucogenic amino acid may also be a ketogenic amino acid.

Accepted Answer

A) True 
 B)False  True

Question 4

Transamination removes the amino group from an amino acid, leaving a carbon skeleton that contains only carbon, hydrogen, and oxygen atoms.

Accepted Answer

A) True 
 B)False

Question 5

Glucosamine, shown below, is a competitive inhibitor of the enzyme hexokinase, which catalyzes the phosphorylation of glucose in the first step of glycolysis (Eqn. 1 below). Which statement best describes the inhibition by glucosamine?

Accepted Answer

A) Glucosamine reacts with glucose, preventing glucose from binding to the active site of hexokinase. 
B) Glucosamine binds to the active site of hexokinase, preventing glucose from binding. 
C) Glucosamine stabilizes the active site of hexokinase, preventing glucose 6-phosphate from being released. 
D) Glucosamine binds to the surface of hexokinase, causing a change in shape of the enzyme and the active site, preventing glucose from binding. 
A) Glucosamine reacts with glucose, preventing glucose from binding to the active site of hexokinase. 
B) Glucosamine binds to the active site of hexokinase, preventing glucose from binding. 
C) Glucosamine stabilizes the active site of hexokinase, preventing glucose 6-phosphate from being released. 
D) Glucosamine binds to the surface of hexokinase, causing a change in shape of the enzyme and the active site, preventing glucose from binding.

Question 6

How is pyruvate converted to acetyl CoA?

Accepted Answer

A) under aerobic conditions 
B) under anaerobic conditions 
C) during fermentation 
D) This conversion is favorable under all of the conditions above. 
A) under aerobic conditions 
B) under anaerobic conditions 
C) during fermentation 
D) This conversion is favorable under all of the conditions above.

Question 7

Individuals with galactosemia lack one of the enzymes necessary for converting galactose to glucose 6-phosphate.

Accepted Answer

A) True 
 B)False

Question 8

$\beta$-Oxidation of a fatty acid requires how many steps to cleave a two carbon acetyl CoA unit from the starting acyl CoA?

Accepted Answer

A) 2 
B) 4 
C) 8 
D) 10 
E) The number of steps required is dependent on the identity of the starting acyl CoA. 
A) 2 
B) 4 
C) 8 
D) 10 
E) The number of steps required is dependent on the identity of the starting acyl CoA.

Question 9

A kinase enzyme catalyzes the transfer of a phosphate group from one substrate to another.

Accepted Answer

A) True 
 B)False

Question 10

In the Cori cycle, compounds are cycled _____

Accepted Answer

A) from the muscles to the kidneys and back to the muscles. 
B) from the muscles to the liver and back to the muscles. 
C) from the kidneys to the liver and back to the kidneys. 
D) from the liver to the brain and back to the liver. 
A) from the muscles to the kidneys and back to the muscles. 
B) from the muscles to the liver and back to the muscles. 
C) from the kidneys to the liver and back to the kidneys. 
D) from the liver to the brain and back to the liver.

Question 11

Step [9] in glycolysis, shown below, involves the dehydration of 2-phosphoglycerate. What is the structure of the dehydration product?

Accepted Answer

A)    
B)    
C)    
D)    
A)    
B)    
C)    
D)

Question 12

What metabolic intermediate is formed from the carbon skeleton of the amino acid asparagine?

Accepted Answer

A) $\alpha$-ketoglutarate 
B) oxaloacetate 
C) citrate 
D) succinyl CoA 
E) fumarate 
A) $\alpha$-ketoglutarate 
B) oxaloacetate 
C) citrate 
D) succinyl CoA 
E) fumarate

Question 13

Transamination is the transfer of an amino group from a(n)_____to a(n)_____, usually $\alpha$-ketoglutarate.

Accepted Answer

amino acid

Question 14

Where does gluconeogenesis take place?

Accepted Answer

A) in the brain 
B) in the muscle tissue 
C) in the liver 
D) in the kidney 
E) Gluconeogenesis takes place in all of the locations listed above. 
A) in the brain 
B) in the muscle tissue 
C) in the liver 
D) in the kidney 
E) Gluconeogenesis takes place in all of the locations listed above.

Question 15

The breakdown of amino acids forms NH4+, which enters the urea cycle to form urea, and a carbon skeleton that is metabolized to either pyruvate, acetyl CoA, or an intermediate in the citric acid cycle.

Accepted Answer

A) True 
 B)False

Question 16

Glucogenic amino acids _____.

Accepted Answer

A) are converted to acetyl CoA. 
B) are converted to glucose. 
C) are catabolized to pyruvate or an intermediate in the citric acid cycle. 
D) can be converted to ketone bodies. 
A) are converted to acetyl CoA. 
B) are converted to glucose. 
C) are catabolized to pyruvate or an intermediate in the citric acid cycle. 
D) can be converted to ketone bodies.

Question 17

Pyruvate is converted to _____ under anaerobic conditions.

Accepted Answer

lactate or

Question 18

When oxygen is plentiful, pyruvate is converted to acetyl CoA, which can enter the citric acid cycle.

Accepted Answer

A) True 
 B)False

Question 19

The glycerol formed from triacylglycerol hydrolysis is converted in two steps to dihydroxyacetone phosphate.

Accepted Answer

A) True 
 B)False

Question 20

_____ and _____ are obtained by the hydrolysis of the disaccharide sucrose, which is found in sugar beets and sugarcane.

Accepted Answer

The answer of _____ and _____ are obtained by the...

Exam 24: Carbohydrate, Lipid, and Protein Metabolism

Fermentation is the aerobic conversion of glucose to ethanol and CO2.

Which process requires the coenzyme NADH?

A glucogenic amino acid may also be a ketogenic amino acid.

Transamination removes the amino group from an amino acid, leaving a carbon skeleton that contains only carbon, hydrogen, and oxygen atoms.

Glucosamine, shown below, is a competitive inhibitor of the enzyme hexokinase, which catalyzes the phosphorylation of glucose in the first step of glycolysis (Eqn. 1 below). Which statement best describes the inhibition by glucosamine?

How is pyruvate converted to acetyl CoA?

Individuals with galactosemia lack one of the enzymes necessary for converting galactose to glucose 6-phosphate.

β\betaβ -Oxidation of a fatty acid requires how many steps to cleave a two carbon acetyl CoA unit from the starting acyl CoA?

A kinase enzyme catalyzes the transfer of a phosphate group from one substrate to another.

In the Cori cycle, compounds are cycled _____

Step [9] in glycolysis, shown below, involves the dehydration of 2-phosphoglycerate. What is the structure of the dehydration product?

What metabolic intermediate is formed from the carbon skeleton of the amino acid asparagine?

Transamination is the transfer of an amino group from a(n)_____to a(n)_____, usually α\alphaα -ketoglutarate.

Where does gluconeogenesis take place?

The breakdown of amino acids forms NH4+, which enters the urea cycle to form urea, and a carbon skeleton that is metabolized to either pyruvate, acetyl CoA, or an intermediate in the citric acid cycle.

Glucogenic amino acids _____.

Pyruvate is converted to _____ under anaerobic conditions.

When oxygen is plentiful, pyruvate is converted to acetyl CoA, which can enter the citric acid cycle.

The glycerol formed from triacylglycerol hydrolysis is converted in two steps to dihydroxyacetone phosphate.

_____ and _____ are obtained by the hydrolysis of the disaccharide sucrose, which is found in sugar beets and sugarcane.

Matter and Measurement

Atoms and the Periodic Table

Ionic Compounds

Covalent Compounds

Chemical Reactions

Energy Changes, Reaction Rates, and Equilibrium

Gases, Liquids, and Solids

Solutions

Acids and Bases

Nuclear Chemistry

Introduction to Organic Molecules and Functional Groups

Alkanes

Unsaturated Hydrocarbons

Organic Compounds That Contain Oxygen, Halogen, or Sulfur

The Three-Dimensional Shape of Molecules

Aldehydes and Ketones

Carboxylic Acids, Esters, and Amides

Amines and Neurotransmitters

Lipids

Carbohydrates

Amino Acids, Proteins, and Enzymes

Nucleic Acids and Protein Synthesis

Digestion and the Conversion of Food Into Energy

Filters

Fermentation is the aerobic conversion of glucose to ethanol and CO₂.

$\beta$ -Oxidation of a fatty acid requires how many steps to cleave a two carbon acetyl CoA unit from the starting acyl CoA?

Transamination is the transfer of an amino group from a(n)_to a(n)_, usually $\alpha$ -ketoglutarate.

The breakdown of amino acids forms NH₄⁺, which enters the urea cycle to form urea, and a carbon skeleton that is metabolized to either pyruvate, acetyl CoA, or an intermediate in the citric acid cycle.

_ and _ are obtained by the hydrolysis of the disaccharide sucrose, which is found in sugar beets and sugarcane.