Question 1

The enzyme phosphoglycerate mutase operates at $\Delta$G ≈ 0 kJ/mol. That indicates that the reversibility of that reaction

Accepted Answer

A)  is spontaneous. 
B)  occurs rapidly. 
C)  occurs at equilibrium. 
D)  is nonspontaneous. 
A)  is spontaneous. 
B)  occurs rapidly. 
C)  occurs at equilibrium. 
D)  is nonspontaneous.

Question 2

The first reaction in glycolysis that produces a high-energy compound is catalyzed by

Accepted Answer

A)  aldolase. 
B)  triose phosphate isomerase. 
C)  enolase. 
D)  phosphofructokinase-1. 
A)  aldolase. 
B)  triose phosphate isomerase. 
C)  enolase. 
D)  phosphofructokinase-1.

Question 3

Which of the following best defines substrate-level phosphorylation?

Accepted Answer

A)  direct transfer of a Pi to an ADP 
B)  direct transfer of a Pi to an ATP 
C)  indirect transfer of a Pi to an ATP 
D)  indirect transfer of a Pi to glucose 
A)  direct transfer of a Pi to an ADP 
B)  direct transfer of a Pi to an ATP 
C)  indirect transfer of a Pi to an ATP 
D)  indirect transfer of a Pi to glucose

Question 4

How can an unfavorable reaction ($\Delta$G$\degree$'  > 0) still occur in a metabolic pathway?

Accepted Answer

A)  Link it to another unfavorable reaction. 
B)  Link it to a favorable reaction. 
C)  They cannot be used in metabolic pathway reactions. 
D)  Increase the temperature of the reaction. 
A)  Link it to another unfavorable reaction. 
B)  Link it to a favorable reaction. 
C)  They cannot be used in metabolic pathway reactions. 
D)  Increase the temperature of the reaction.

Question 5

Illustrate both the Fisher and Haworth projections for glucose and fructose

Accepted Answer

The answer of Illustrate both the Fisher and Haworth projections...

Question 6

List the 10 enzymes required for glycolysis.

Accepted Answer

Hexokinase, phosphoglucoisomerase, phosp

Question 7

Which of the following metabolic conversions is considered to be the major control point of glycolysis?

Accepted Answer

A)  fructose-1,6-bisphosphate $\rightarrow$dihydroxyacetone phosphate + glyceraldehyde-3-phosphate 
B)  1,3-Bisphosphoglycerate + ADP $\rightarrow$3-Phosphoglycerate + ATP 
C)  2-phosphoglyerate $\rightarrow$phosphoenolpyruvate 
D)  fructose-6-phosphate $\rightarrow$fructose-1,6-bisphosphate 
A)  fructose-1,6-bisphosphate $\rightarrow$dihydroxyacetone phosphate + glyceraldehyde-3-phosphate 
B)  1,3-Bisphosphoglycerate + ADP $\rightarrow$3-Phosphoglycerate + ATP 
C)  2-phosphoglyerate $\rightarrow$phosphoenolpyruvate 
D)  fructose-6-phosphate $\rightarrow$fructose-1,6-bisphosphate

Question 8

The glycolytic pathway is responsible for passing molecules to which other pathways?

Accepted Answer

A)  citrate cycle and nitrogen fixation 
B)  photosynthesis and oxidative phosphorylation 
C)  citrate cycle and oxidative phosphorylation 
D)  urea cycle and fatty acid synthesis 
A)  citrate cycle and nitrogen fixation 
B)  photosynthesis and oxidative phosphorylation 
C)  citrate cycle and oxidative phosphorylation 
D)  urea cycle and fatty acid synthesis

Question 9

Draw the mechanism for bisphosphoglycerate mutase and explain how this reaction has an effect on oxygen transport.

Accepted Answer

As shown in Figure 9.34, bisphosphoglyce

Question 10

In glycolysis, fructose 1,6-bisphosphate is converted to two products with a standard free-energy change ($\Delta$G ' $\degree$) of 23.8 kJ/mol. Under what conditions (encountered in erythrocytes) will the free-energy change ($\Delta$G) be negative, enabling the reaction to proceed to products?

Accepted Answer

A)  The free-energy change will be negative if the concentrations of the two products are high relative to that of fructose 1,6-bisphosphate. 
B)  The reaction will not go to the right spontaneously under any conditions because the $\Delta$G ' $\degree$ is positive. 
C)  Under standard conditions, enough energy is released to drive the reaction to the right. 
D)  The free-energy change will be negative when there is a high concentration of fructose 1,6-bisphosphate relative to the concentration of products. 
A)  The free-energy change will be negative if the concentrations of the two products are high relative to that of fructose 1,6-bisphosphate. 
B)  The reaction will not go to the right spontaneously under any conditions because the $\Delta$G ' $\degree$ is positive. 
C)  Under standard conditions, enough energy is released to drive the reaction to the right. 
D)  The free-energy change will be negative when there is a high concentration of fructose 1,6-bisphosphate relative to the concentration of products.

Question 11

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 12

Which of following is an anomeric pair?

Accepted Answer

A)  "D-glucose and D-fructose" 
B)  "D-glucose and L-fructose" 
C)  "D-glucose and L-glucose" 
D)  "$\alpha$-D-glucose and $\beta$-D-glucose" 
A)  "D-glucose and D-fructose" 
B)  "D-glucose and L-fructose" 
C)  "D-glucose and L-glucose" 
D)  "$\alpha$-D-glucose and $\beta$-D-glucose"

Question 13

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 14

During glycolysis, the steps between glucose and formation of glyceraldehyde-3-phosphate

Accepted Answer

A)  consume 2 ATP and 2 NADH. 
B)  consume 2 ATP. 
C)  produce 2 ADP and 2 NADH. 
D)  produce 2 ATP and 2 NADH. 
A)  consume 2 ATP and 2 NADH. 
B)  consume 2 ATP. 
C)  produce 2 ADP and 2 NADH. 
D)  produce 2 ATP and 2 NADH.

Question 15

Flux is defined as the rate at which is/are interconverted.

Accepted Answer

A)  enzymes 
B)  metabolites 
C)  sugars 
D)  energy 
A)  enzymes 
B)  metabolites 
C)  sugars 
D)  energy

Question 16

What is the potential metabolic fate of pyruvate under aerobic conditions?

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 17

Which of the following pathways are found in both plants and animals?

Accepted Answer

A)  photosynthesis and carbon fixation 
B)  urea cycle 
C)  nitrogen fixation 
D)  citrate cycle 
A)  photosynthesis and carbon fixation 
B)  urea cycle 
C)  nitrogen fixation 
D)  citrate cycle

Question 18

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 19

To produce 4 ATP requires 122 kJ/mol. Which reactions in the glycolytic pathway produce enough energy to be able to overcome this deficit?

Accepted Answer

A)  hexokinase, phosphofructokinase-1, and pyruvate kina 
B)  hexokinase, phosphofructokinase-1, and pyruvate kinase 
C)  phosphofructokinase-1, aldolase, and pyruvate kinase 
D)  hexokinase, enolase, and pyruvate kinase 
A)  hexokinase, phosphofructokinase-1, and pyruvate kina 
B)  hexokinase, phosphofructokinase-1, and pyruvate kinase 
C)  phosphofructokinase-1, aldolase, and pyruvate kinase 
D)  hexokinase, enolase, and pyruvate kinase

Question 20

What does glycolysis accomplish for the cell?

Accepted Answer

A)  It generates ADP for the cell to be used in other cycles. 
B)  It generates ATP and pyruvate for the cell to be used in other cycles. 
C)  It generates glucose to be used for storage. 
D)  It generates CO2 that is exhaled. 
A)  It generates ADP for the cell to be used in other cycles. 
B)  It generates ATP and pyruvate for the cell to be used in other cycles. 
C)  It generates glucose to be used for storage. 
D)  It generates CO2 that is exhaled.

Exam 9: Glycolysis: a Paradigm of Metabolic Regulation

The enzyme phosphoglycerate mutase operates at Δ\DeltaΔ G ≈ 0 kJ/mol. That indicates that the reversibility of that reaction

The first reaction in glycolysis that produces a high-energy compound is catalyzed by

Which of the following best defines substrate-level phosphorylation?

How can an unfavorable reaction ( Δ\DeltaΔ G °\degree° ' > 0) still occur in a metabolic pathway?

Illustrate both the Fisher and Haworth projections for glucose and fructose

List the 10 enzymes required for glycolysis.

Which of the following metabolic conversions is considered to be the major control point of glycolysis?

The glycolytic pathway is responsible for passing molecules to which other pathways?

Draw the mechanism for bisphosphoglycerate mutase and explain how this reaction has an effect on oxygen transport.

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

Which of following is an anomeric pair?

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

During glycolysis, the steps between glucose and formation of glyceraldehyde-3-phosphate

Flux is defined as the rate at which is/are interconverted.

What is the potential metabolic fate of pyruvate under aerobic conditions?

Which of the following pathways are found in both plants and animals?

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

To produce 4 ATP requires 122 kJ/mol. Which reactions in the glycolytic pathway produce enough energy to be able to overcome this deficit?

What does glycolysis accomplish for the cell?

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

The enzyme phosphoglycerate mutase operates at $\Delta$ G ≈ 0 kJ/mol. That indicates that the reversibility of that reaction

How can an unfavorable reaction ( $\Delta$ G $\degree$ ^' > 0) still occur in a metabolic pathway?