Question 1

What are the primary metabolic fates of pyruvate?

Accepted Answer

A)  ethanol 
B)  lactate 
C)  acetyl CoA 
D)  All of the answers are correct. 
E)  ethanol and lactate 
A)  ethanol 
B)  lactate 
C)  acetyl CoA 
D)  All of the answers are correct. 
E)  ethanol and lactate D

Question 2

What two functions are attributed to substrate cycles?

Accepted Answer

The substrate cycles regulate glycolytic path flux by amplifying metabolic signals,and they generate body heat produced by the hydrolysis of ATP.

Question 3

What two 3-carbon molecules are generated by the cleavage of fructose-1,6-bisphosphate?

Accepted Answer

A)  glyceraldehyde-3-phosphate and 3-phosphoglycerate 
B)  glyceraldehyde-3-phosphate and dihydroxyacetone phosphate 
C)  pyruvate and phosphoenolpyruvate 
D)  enolase and 2-phosphoglycerate 
E)  glyceraldehyde-3-phosphate and pyruvate 
A)  glyceraldehyde-3-phosphate and 3-phosphoglycerate 
B)  glyceraldehyde-3-phosphate and dihydroxyacetone phosphate 
C)  pyruvate and phosphoenolpyruvate 
D)  enolase and 2-phosphoglycerate 
E)  glyceraldehyde-3-phosphate and pyruvate B

Question 4

A potent allosteric activator of liver phosphofructokinase is _____________________,which is produced from fructose-6-phosphate by PFK2.

Accepted Answer

fructose-2

Question 5

What reaction is catalyzed by aldolase?

Accepted Answer

A)  isomerization of DHAP to GAP 
B)  hydrolysis of either GAP or DHAP 
C)  reversible cleavage of F-1,6-BP to DHAP and GAP 
D)  cleavage of DHAP to GAP 
E)  irreversible aldol condensation of DHAP and GAP 
A)  isomerization of DHAP to GAP 
B)  hydrolysis of either GAP or DHAP 
C)  reversible cleavage of F-1,6-BP to DHAP and GAP 
D)  cleavage of DHAP to GAP 
E)  irreversible aldol condensation of DHAP and GAP

Question 6

Which of the following must be regenerated for glycolysis to proceed?

Accepted Answer

A)  pyruvate 
B)  ATP 
C)  NAD+ 
D)  UDP-glucose 
E)  All of the answers are correct. 
A)  pyruvate 
B)  ATP 
C)  NAD+ 
D)  UDP-glucose 
E)  All of the answers are correct.

Question 7

Describe the biochemical explanation for galactosemia.

Accepted Answer

Galactose is metabolized by conversion t

Question 8

What transporter is responsible for fructose uptake in the intestine?

Accepted Answer

A)  GLUT1 
B)  GLUT2 
C)  GLUT3 
D)  GLUT4 
E)  GLUT5 
A)  GLUT1 
B)  GLUT2 
C)  GLUT3 
D)  GLUT4 
E)  GLUT5

Question 9

The catalytic mechanism of the isomerization of a ketose into an aldose proceeds through an _________________ intermediate.

Accepted Answer

The answer of The catalytic mechanism of the isomerization of...

Question 10

What astounding discovery was made by the Buchners?

Accepted Answer

When the Buchners demonstrated

Question 11

Describe the two isoforms of lactate dehydrogenase.

Accepted Answer

Two forms exist,called M and H,which pre

Question 12

Why do muscles need to generate ATP under aerobic and anaerobic conditions?

Accepted Answer

Muscles initially function aerobically.H

Question 13

How is the conversion of phosphoenolpyruvate to pyruvate accompanied by ATP formation?

Accepted Answer

The enol phosphate possesses v

Question 14

Which of the following is an allosteric inhibitor of gluconeogenesis?

Accepted Answer

A)  NADH 
B)  ATP 
C)  AMP 
D)  fructose 6-phosphate 
E)  phosphoenolpyruvate 
A)  NADH 
B)  ATP 
C)  AMP 
D)  fructose 6-phosphate 
E)  phosphoenolpyruvate

Question 15

Two primary raw materials for gluconeogenesis in the human liver are

Accepted Answer

A)  galactose and sucrose. 
B)  acetate and oxaloacetate. 
C)  lactate and alanine. 
D)  fructose and alanine. 
E)  lactose and lactate. 
A)  galactose and sucrose. 
B)  acetate and oxaloacetate. 
C)  lactate and alanine. 
D)  fructose and alanine. 
E)  lactose and lactate.

Question 16

Which of the following are reasons that glucose is a common metabolic fuel used by living organisms?

Accepted Answer

A)  In its stable ring structure, glucose is unlikely to nonezymatically glycosylate proteins. 
B)  It is one of the fuels formed under prebiotic conditions, thus available for primitive biochemical systems. 
C)  It is the only sugar used by the brain and kidney as a fuel source. 
D)  It is a ketose and thus a nonreducing sugar. 
E)  Both A and B are correct. 
A)  In its stable ring structure, glucose is unlikely to nonezymatically glycosylate proteins. 
B)  It is one of the fuels formed under prebiotic conditions, thus available for primitive biochemical systems. 
C)  It is the only sugar used by the brain and kidney as a fuel source. 
D)  It is a ketose and thus a nonreducing sugar. 
E)  Both A and B are correct.

Question 17

Which of the following intermediates is needed for the conversion of galactose into glucose by reacting with galactose 1-phosphate?

Accepted Answer

A)  glucose 1-phosphate 
B)  fructose 6-phosphate 
C)  glucose 6-phosphate 
D)  UDP-galactose 
E)  UDP-glucose 
A)  glucose 1-phosphate 
B)  fructose 6-phosphate 
C)  glucose 6-phosphate 
D)  UDP-galactose 
E)  UDP-glucose

Question 18

What is the purpose of phosphorylating glucose in the cytosol?

Accepted Answer

A)  to trap glucose in the cell 
B)  to destabilize glucose and facilitate the next series of metabolic steps 
C)  to convert it to a more soluble form 
D)  to slow the transport of glucose into the cell 
E)  Both A and B are correct. 
A)  to trap glucose in the cell 
B)  to destabilize glucose and facilitate the next series of metabolic steps 
C)  to convert it to a more soluble form 
D)  to slow the transport of glucose into the cell 
E)  Both A and B are correct.

Question 19

What nutrient is required for the carboxylation of pyruvate in humans?

Accepted Answer

A)  biotin 
B)  thiamine 
C)  riboflavin 
D)  niacin 
E)  folic acid 
A)  biotin 
B)  thiamine 
C)  riboflavin 
D)  niacin 
E)  folic acid

Question 20

The key enzyme that regulates the pace of glycolysis is ____________________.

Accepted Answer

The answer of The key enzyme that regulates the pace...

Exam 16: Glycolysis and Gluconeogenesis

What are the primary metabolic fates of pyruvate?

What two functions are attributed to substrate cycles?

What two 3-carbon molecules are generated by the cleavage of fructose-1,6-bisphosphate?

A potent allosteric activator of liver phosphofructokinase is _____________________,which is produced from fructose-6-phosphate by PFK2.

What reaction is catalyzed by aldolase?

Which of the following must be regenerated for glycolysis to proceed?

Describe the biochemical explanation for galactosemia.

What transporter is responsible for fructose uptake in the intestine?

The catalytic mechanism of the isomerization of a ketose into an aldose proceeds through an _________________ intermediate.

What astounding discovery was made by the Buchners?

Describe the two isoforms of lactate dehydrogenase.

Why do muscles need to generate ATP under aerobic and anaerobic conditions?

How is the conversion of phosphoenolpyruvate to pyruvate accompanied by ATP formation?

Which of the following is an allosteric inhibitor of gluconeogenesis?

Two primary raw materials for gluconeogenesis in the human liver are

Which of the following are reasons that glucose is a common metabolic fuel used by living organisms?

Which of the following intermediates is needed for the conversion of galactose into glucose by reacting with galactose 1-phosphate?

What is the purpose of phosphorylating glucose in the cytosol?

What nutrient is required for the carboxylation of pyruvate in humans?

The key enzyme that regulates the pace of glycolysis is ____________________.

Biochemistry: An Evolving Science

Protein Composition and Structure

Exploring Proteins and Proteomes

DNA, RNA, and the Flow of Genetic Information

Exploring Genes and Genomes

Exploring Evolution and Bioinformatics

Hemoglobin: a Portrait of a Protein in Action

Enzymes: Basic Concepts and Kinetics

Catalytic Strategies

Regulatory Strategies

Carbohydrates

Lipids and Cell Membranes

Membrane Channels and Pumps

Signal-Transduction Pathways

Metabolism: Basic Concepts and Design

The Citric Acid Cycle

Oxidative Phosphorylation

The Light Reactions of Photosynthesis

The Calvin Cycle and the Pentose Phosphate Pathway

Glycogen Metabolism

Fatty Acid Metabolism

Protein Turnover and Amino Acid Catabolism

The Biosynthesis of Amino Acids

Nucleotide Biosynthesis

Biosynthesis of Membrane Lipids and Steroids

The Integration of Metabolism

DNA Replication, repair, and Recombination

RNA Synthesis and Processing

Protein Synthesis

The Control of Gene Expression in Prokaryotes

The Control of Gene Expression in Eukaryotes

Sensory Systems

The Immune System

Molecular Motors

Drug Development

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