Question 1

Demonstrate the cyclization of linear glucose to cyclic glucopyranose.

Accepted Answer

The answer of Demonstrate the cyclization of linear glucose to...

Question 2

Glucose and fructose are both C6H12O6.What is the structural difference between them?

Accepted Answer

A)  Glucose is a five-membered ring and fructose is a six-membered ring. 
B)  Fructose is a five-membered ring and glucose is a six-membered ring. 
C)  Glucose is a linear molecule and fructose is a ring. 
D)  Glucose is found in the boat conformation and fructose is a chair conformation. 
A)  Glucose is a five-membered ring and fructose is a six-membered ring. 
B)  Fructose is a five-membered ring and glucose is a six-membered ring. 
C)  Glucose is a linear molecule and fructose is a ring. 
D)  Glucose is found in the boat conformation and fructose is a chair conformation. B

Question 3

Describe how molecules such as maltose can enter glycolysis.

Accepted Answer

Maltose is cleaved by maltase to form two molecules of glucose.Glucose can then enter glycolysis.See Figure 9.48 for the entire pathway.

Question 4

Benedict's test is a redox reaction between glucose and copper.Draw the reaction between glucose and copper.

Accepted Answer

See Figure 9.13a.The glucose i

Question 5

Differentiate among epimers,anomers,and isomers.

Accepted Answer

Epimers are two monosaccharides of same

Question 6

Draw the five steps required by aldolase to convert fructose 1,6-bisphosate into glyceraldehyde-3-phosphate and dihydroxyacetone phosphate.

Accepted Answer

See Figure

Question 7

Which of the following is the correct net reaction for glycolysis?

Accepted Answer

A)  glucose + 2 ATP  2 lactate +2ADP+2Pi 
B)  glucose + 2 ADP + 2 Pi + 2 NAD+  2 pyruvate + 2 ATP + 2 NADH + 4 H+ 
C)  glucose + 2 ADP + 2 Pi  2CH3CH2OH + 2 CO2 + 2 ATP 
D)  glucose + 2 ADP + 2 Pi + 2 NAD+  2 pyruvate + 2 ATP + 2 NADH + 2 H+ + 2H2O 
A)  glucose + 2 ATP  2 lactate +2ADP+2Pi 
B)  glucose + 2 ADP + 2 Pi + 2 NAD+  2 pyruvate + 2 ATP + 2 NADH + 4 H+ 
C)  glucose + 2 ADP + 2 Pi  2CH3CH2OH + 2 CO2 + 2 ATP 
D)  glucose + 2 ADP + 2 Pi + 2 NAD+  2 pyruvate + 2 ATP + 2 NADH + 2 H+ + 2H2O

Question 8

Distinguish between D and L isomers.

Accepted Answer

A)  D is right handed and L is left handed. 
B)  D is left handed and L is right handed. 
C)  D and L only differ in the position of one chiral center. 
D)  D is the boat conformation and L is the chair conformation. 
A)  D is right handed and L is left handed. 
B)  D is left handed and L is right handed. 
C)  D and L only differ in the position of one chiral center. 
D)  D is the boat conformation and L is the chair conformation.

Question 9

What is the potential metabolic fate of pyruvate during strenuous exercise?

Accepted Answer

A)  produce lactate 
B)  produce ethanol 
C)  produce carbon dioxide and water 
D)  produce glucose 
A)  produce lactate 
B)  produce ethanol 
C)  produce carbon dioxide and water 
D)  produce glucose

Question 10

Calculate the net   for the following series of reactions:

Accepted Answer

A)  14 kJ/mol 
B)  -6 kJ/mol 
C)  6 kJ/mol 
D)  0 kJ/mol 
A)  14 kJ/mol 
B)  -6 kJ/mol 
C)  6 kJ/mol 
D)  0 kJ/mol

Question 11

Fructose-1,6-bisphosphate is cleaved by aldolase.What is required for the reaction to proceed?

Accepted Answer

A)  production of endergonic intermediate 
B)  substrate phosphorylation 
C)  cleaving of high-energy phosphate bond 
D)  formation of Schiff base intermediate 
A)  production of endergonic intermediate 
B)  substrate phosphorylation 
C)  cleaving of high-energy phosphate bond 
D)  formation of Schiff base intermediate

Question 12

NAD+ is required for the oxidative step of glycolysis.Briefly discuss how NAD+ is regenerated from NADH under aerobic and anaerobic conditions.

Accepted Answer

Under aerobic conditions,electrons pass

Question 13

What effect do elevated levels of ATP have on glycolysis?

Accepted Answer

A)  decrease the affinity of PFK-1 for fructose-6-P and slow rate of the pathway 
B)  increase the affinity of PFK-1 for fructose-6-P and increase the rate of the pathway 
C)  increase the concentration of PFK-1 in the R-state 
D)  increase the concentration of glucose entering glycolysis 
A)  decrease the affinity of PFK-1 for fructose-6-P and slow rate of the pathway 
B)  increase the affinity of PFK-1 for fructose-6-P and increase the rate of the pathway 
C)  increase the concentration of PFK-1 in the R-state 
D)  increase the concentration of glucose entering glycolysis

Question 14

List three common disaccharides in nature and draw the structures of each.

Accepted Answer

Lactose,sucrose,treh

Question 15

If blood glucose levels are elevated,what does glucokinase do in response?

Accepted Answer

A)  inhibits glycolysis 
B)  stimulates the production of more hexokinase 
C)  stimulates the release of insulin 
D)  inhibits production of 2,3-BPG 
A)  inhibits glycolysis 
B)  stimulates the production of more hexokinase 
C)  stimulates the release of insulin 
D)  inhibits production of 2,3-BPG

Question 16

Anomers differ from each other by changes at the __________ carbon.

Accepted Answer

A)  chiral 
B)  C-2 
C)  C-3 
D)  C-1 
A)  chiral 
B)  C-2 
C)  C-3 
D)  C-1

Question 17

Describe galactose metabolism.If a person has galactosemia,what does that indicate about his or her galactose metabolic pathway?

Accepted Answer

First galactose is phosphorylated by gal

Question 18

In which of the following metabolic conversions is ATP "consumed" during glycolysis?

Accepted Answer

A)  1,3-Bisphosphoglycerate  3-phosphoglycerate 
B)  glucose  Glucose-6-phosphate 
C)  2-Phosphoglycerate  3-phosphoglycerate 
D)  glucose-6-phosphate  Fructose-6-phosphate 
A)  1,3-Bisphosphoglycerate  3-phosphoglycerate 
B)  glucose  Glucose-6-phosphate 
C)  2-Phosphoglycerate  3-phosphoglycerate 
D)  glucose-6-phosphate  Fructose-6-phosphate

Question 19

If a person has a deficiency in fructose-1-P,what effects does that have on the body?

Accepted Answer

A)  Fructose-6-P concentrations increase. 
B)  Fructose-6-P is depleted. 
C)  ATP concentrations increase. 
D)  Glucose-6-P concentrations increase. 
A)  Fructose-6-P concentrations increase. 
B)  Fructose-6-P is depleted. 
C)  ATP concentrations increase. 
D)  Glucose-6-P concentrations increase.

Question 20

A shared intermediate can be defined as a molecule that is

Accepted Answer

A)  a reactant in a pathway. 
B)  the final product of a pathway. 
C)  the final product of a pathway and the reactant of the next pathway. 
D)  favorable to produce. 
A)  a reactant in a pathway. 
B)  the final product of a pathway. 
C)  the final product of a pathway and the reactant of the next pathway. 
D)  favorable to produce.

Exam 9: Glycolysis: a Paradigm of Metabolic Regulation

Demonstrate the cyclization of linear glucose to cyclic glucopyranose.

Glucose and fructose are both C6H12O6.What is the structural difference between them?

Describe how molecules such as maltose can enter glycolysis.

Benedict's test is a redox reaction between glucose and copper.Draw the reaction between glucose and copper.

Differentiate among epimers,anomers,and isomers.

Draw the five steps required by aldolase to convert fructose 1,6-bisphosate into glyceraldehyde-3-phosphate and dihydroxyacetone phosphate.

Which of the following is the correct net reaction for glycolysis?

Distinguish between D and L isomers.

What is the potential metabolic fate of pyruvate during strenuous exercise?

Calculate the net for the following series of reactions:

Fructose-1,6-bisphosphate is cleaved by aldolase.What is required for the reaction to proceed?

NAD+ is required for the oxidative step of glycolysis.Briefly discuss how NAD+ is regenerated from NADH under aerobic and anaerobic conditions.

What effect do elevated levels of ATP have on glycolysis?

List three common disaccharides in nature and draw the structures of each.

If blood glucose levels are elevated,what does glucokinase do in response?

Anomers differ from each other by changes at the __________ carbon.

Describe galactose metabolism.If a person has galactosemia,what does that indicate about his or her galactose metabolic pathway?

In which of the following metabolic conversions is ATP "consumed" during glycolysis?

If a person has a deficiency in fructose-1-P,what effects does that have on the body?

A shared intermediate can be defined as a molecule that is

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

The Citrate Cycle

Oxidative Phosphorylation

Photosynthesis

Carbohydrate Structure and Function

Carbohydrate Metabolism

Lipid Structure and Function

Lipid Metabolism

Amino Acid 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

Glucose and fructose are both C₆H₁₂O₆.What is the structural difference between them?

NAD⁺ is required for the oxidative step of glycolysis.Briefly discuss how NAD⁺ is regenerated from NADH under aerobic and anaerobic conditions.