Question 1

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

Accepted Answer

A)  It has a stable ring structure and is unlikely to glycosylate proteins. 
B)  It has been found as one of the monosaccharides formed under prebiotic conditions. 
C)  It is the only sugar used by the brain. 
D)  A and B. 
E)  A, B, and C. 
A)  It has a stable ring structure and is unlikely to glycosylate proteins. 
B)  It has been found as one of the monosaccharides formed under prebiotic conditions. 
C)  It is the only sugar used by the brain. 
D)  A and B. 
E)  A, B, and C.

Question 2

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

Accepted Answer

The enol phosphate possesses v

Question 3

Which two isomerization reactions occur in glycolysis? Why are these steps necessary?

Accepted Answer

Glucose 6-phosphate is isomerized to fru

Question 4

Why is it more sensible for phosphofructokinase, rather than hexokinase, to be an important control step?

Accepted Answer

Phosphofructokinase catalyzes the first

Question 5

Both hexokinase and glucokinase phosphorylate glucose. The function of glucokinase is to phosphorylate glucose in liver cells as a means to regulate blood-sugar levels. Would you expect its Km to be higher or lower than that of hexokinase?

Accepted Answer

Glucokinase must be responsive to elevat

Question 6

What are fermentations?

Accepted Answer

Fermentations are ATP-generati

Question 7

______________ are enzymes that catalyze the transfer of a phosphoryl group from ATP to an acceptor.

Accepted Answer

The answer of ______________ are enzymes that catalyze the transfer...

Question 8

Choose the correct answer from the list below. Not all of the answers will be used.
-An allosteric activator of glycolysis is ____________.

Accepted Answer

A) obligate anaerobes 
B) AMP 
C) pyruvate 
D) NAD+ 
E) glucose
F)UDP-glucose
G)GLUT5
H)facultative anaerobes
I)ATP
J)magnesium
K)galactokinase
L)GLUT2
M)galactose isomerase 
A) obligate anaerobes 
B) AMP 
C) pyruvate 
D) NAD+ 
E) glucose
F)UDP-glucose
G)GLUT5
H)facultative anaerobes
I)ATP
J)magnesium
K)galactokinase
L)GLUT2
M)galactose isomerase

Question 9

How does citrate influence glycolysis?

Accepted Answer

Phosphofructokinase is inhibited by citr

Question 10

Describe how pyruvate kinase regulation occurs and how this is important in the regulation of glycolysis.

Accepted Answer

Pyruvate kinase is allosterically inhibi

Question 11

What are the primary metabolic fates of pyruvate?

Accepted Answer

A)  ethanol 
B)  lactate 
C)  acetyl CoA 
D)  All of the above. 
E)  None of the above. 
A)  ethanol 
B)  lactate 
C)  acetyl CoA 
D)  All of the above. 
E)  None of the above.

Question 12

Describe the two isoforms of pyruvate kinase.

Accepted Answer

The two forms, called M and L,

Question 13

The first irreversible enzymatic reaction unique to a metabolic pathway is called the ______________ step

Accepted Answer

The answer of The first irreversible enzymatic reaction unique to...

Question 14

Lactose intolerance is caused by a deficiency of:

Accepted Answer

A)  lactase. 
B)  elastase 
C)  lactose. 
D)  sucrase. 
E)  None of the above. 
A)  lactase. 
B)  elastase 
C)  lactose. 
D)  sucrase. 
E)  None of the above.

Question 15

Fructose can enter glycolysis at two distinct points, depending on the tissue. How is fructose metabolized in adipose tissue?

Accepted Answer

A)  Fructose is cleaved to two molecules of GAP. 
B)  Fructose is converted to fructose 1-phosphate. 
C)  Fructose is converted to fructose 6-phosphate. 
D)  Fructose is cleaved to GAP and DHAP. 
E)  Fructose is converted to glucose, which enters the pathway. 
A)  Fructose is cleaved to two molecules of GAP. 
B)  Fructose is converted to fructose 1-phosphate. 
C)  Fructose is converted to fructose 6-phosphate. 
D)  Fructose is cleaved to GAP and DHAP. 
E)  Fructose is converted to glucose, which enters the pathway.

Question 16

What is the purpose of phosphorylating glucose in 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)  All of the above. 
E)  A and B 
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)  All of the above. 
E)  A and B

Question 17

Cancer-driven hypoxia brings about the induction of which genes involved in glycolysis?

Accepted Answer

A)  GLUT3 
B)  hexokinase 
C)  aldolase 
D)  All of the above. 
E)  None of the above. 
A)  GLUT3 
B)  hexokinase 
C)  aldolase 
D)  All of the above. 
E)  None of the above.

Question 18

Choose the correct answer from the list below. Not all of the answers will be used.
-The transporter that is responsible for fructose uptake in the intestine is ____________.

Accepted Answer

A) obligate anaerobes 
B) AMP 
C) pyruvate 
D) NAD+ 
E) glucose
F)UDP-glucose
G)GLUT5
H)facultative anaerobes
I)ATP
J)magnesium
K)galactokinase
L)GLUT2
M)galactose isomerase 
A) obligate anaerobes 
B) AMP 
C) pyruvate 
D) NAD+ 
E) glucose
F)UDP-glucose
G)GLUT5
H)facultative anaerobes
I)ATP
J)magnesium
K)galactokinase
L)GLUT2
M)galactose isomerase

Question 19

What is a common mechanistic feature of kinases?

Accepted Answer

A)  Phosphoryl groups are transferred from AMP to an acceptor. 
B)  The binding of substrate induces cleft closing. 
C)  Kinases convert aldoses to ketoses. 
D)  All of the above. 
E)  None of the above. 
A)  Phosphoryl groups are transferred from AMP to an acceptor. 
B)  The binding of substrate induces cleft closing. 
C)  Kinases convert aldoses to ketoses. 
D)  All of the above. 
E)  None of the above.

Question 20

What is substrate-level phosphorylation?

Accepted Answer

A)  phosphorylation of AMP by ATP 
B)  ATP synthesis when the phosphate donor is a substrate with high-phosphoryl-transfer potential 
C)  phosphorylation of glycolytic intermediates 
D)  phosphorylation of ATP coupled to an ion gradient 
E)  ATP and AMP synthesis from two molecules of ADP 
A)  phosphorylation of AMP by ATP 
B)  ATP synthesis when the phosphate donor is a substrate with high-phosphoryl-transfer potential 
C)  phosphorylation of glycolytic intermediates 
D)  phosphorylation of ATP coupled to an ion gradient 
E)  ATP and AMP synthesis from two molecules of ADP

Exam 16: Glycolysis

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

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

Which two isomerization reactions occur in glycolysis? Why are these steps necessary?

Why is it more sensible for phosphofructokinase, rather than hexokinase, to be an important control step?

Both hexokinase and glucokinase phosphorylate glucose. The function of glucokinase is to phosphorylate glucose in liver cells as a means to regulate blood-sugar levels. Would you expect its Km to be higher or lower than that of hexokinase?

What are fermentations?

______________ are enzymes that catalyze the transfer of a phosphoryl group from ATP to an acceptor.

Choose the correct answer from the list below. Not all of the answers will be used. -An allosteric activator of glycolysis is ____________.

How does citrate influence glycolysis?

Describe how pyruvate kinase regulation occurs and how this is important in the regulation of glycolysis.

What are the primary metabolic fates of pyruvate?

Describe the two isoforms of pyruvate kinase.

The first irreversible enzymatic reaction unique to a metabolic pathway is called the ______________ step

Lactose intolerance is caused by a deficiency of:

Fructose can enter glycolysis at two distinct points, depending on the tissue. How is fructose metabolized in adipose tissue?

What is the purpose of phosphorylating glucose in cytosol?

Cancer-driven hypoxia brings about the induction of which genes involved in glycolysis?

Choose the correct answer from the list below. Not all of the answers will be used. -The transporter that is responsible for fructose uptake in the intestine is ____________.

What is a common mechanistic feature of kinases?

What is substrate-level phosphorylation?

Biochemistry and the Unity of Life

Water, Weak Bonds, and the Generation of Order Out of Chaos

Amino Acids

Protein Three-Dimensional Structure

Techniques in Protein Biochemistry

Basic Concepts of Enzyme Action

Kinetics and Regulation

Mechanisms and Inhibitors

Hemoglobin: an Allosteric Protein

Carbohydrates

Lipids

Membrane Structure and Function

Signal Transduction Pathways

Digestion: Turning a Meal Into Cellular Biochemicals

Metabolism: Basic Concepts and Design

Gluconeogenesis

Preparation for the Cycle

Harvesting Electrons From the Cycle

The Electron Transport Chain

The Proton-Motive Force

The Light Reactions

The Calvin Cycle

Glycogen Degradation

Glycogen Synthesis

The Pentose Phosphate Pathway

Fatty Acid Degredation

Fatty Acid Synthesis

Lipid Synthesis

Amino Acid Degradation and the Urea Cycle

Amino Acids Synthesis

Nucleotide Metabolism

The Structure of Informational Macromolecules: Dna and Rna

DNA Replication

DNA Repair and Recombination

RNA Synthesis and Regulation in Prokaryotes

Gene Expression in Eukaryotes

RNA Processing in Eukaryotes

The Genetic Code

The Mechanism of Protein Synthesis

Recombinant DNA Techniques

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