Question 1

Methanol is extremely toxic, but not directly. In the body, it is converted into formaldehyde; that's what's actually the poison. What kind of enzyme catalyses this conversion?

Accepted Answer

A)  a kinase 
B)  an isomerase 
C)  a mutase 
D)  a dehydrogenase 
A)  a kinase 
B)  an isomerase 
C)  a mutase 
D)  a dehydrogenase

Question 2

How many enzymes of glycolysis are control points for the pathway?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  All the enzymes serve as control points. 
A)  1 
B)  2 
C)  3 
D)  4 
E)  All the enzymes serve as control points.

Question 3

The binding of glucose to hexokinase

Accepted Answer

A)  is an example of lock-and-key binding of a substrate to the active site of an enzyme. 
B)  is an example of induced-fit binding of a substrate to the active site of an enzyme. 
C)  differs from the binding of substrates to other kinases. 
D)  is not well characterized. 
A)  is an example of lock-and-key binding of a substrate to the active site of an enzyme. 
B)  is an example of induced-fit binding of a substrate to the active site of an enzyme. 
C)  differs from the binding of substrates to other kinases. 
D)  is not well characterized.

Question 4

Glycolysis

Accepted Answer

A)  does not require O2 to generate energy. 
B)  requires O2 to generate energy. 
C)  is inhibited by O2. 
D)  rate is increased in the presence of O2. 
A)  does not require O2 to generate energy. 
B)  requires O2 to generate energy. 
C)  is inhibited by O2. 
D)  rate is increased in the presence of O2.

Question 5

​ Phosphorylation of fructose 6-phosphate to produce fructose-1,6- bis phosphate happens in the _____ step of glycolysis.

Accepted Answer

A)  first 
B)  second 
C)  third 
D)  fourth 
A)  first 
B)  second 
C)  third 
D)  fourth

Question 6

Consider the following information:   How many molecules of ATP might theoretically have been produced when coupled to the conversion of one molecule phosphoenolpyruvate to pyruvate?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
A)  1 
B)  2 
C)  3 
D)  4

Question 7

In humans, pyruvate can be converted to

Accepted Answer

A)  acetyl-CoA only. 
B)  lactate only. 
C)  ethanol only. 
D)  acetyl-CoA and lactate. 
A)  acetyl-CoA only. 
B)  lactate only. 
C)  ethanol only. 
D)  acetyl-CoA and lactate.

Question 8

Which of the following enzymes forms a thioester using a cysteine residue as a key intermediate?

Accepted Answer

A)  hexokinase 
B)  triose phosphate isomerase 
C)  glyceraldehyde-3-phosphate dehydrogenase 
D)  enolase 
A)  hexokinase 
B)  triose phosphate isomerase 
C)  glyceraldehyde-3-phosphate dehydrogenase 
D)  enolase

Question 9

During glycolysis, enolase , the enzyme that catalyzes the conversion of 2-phophoglycerate to phosphoenolpyruvate requires _____ as a cofactor.

Accepted Answer

A)  Fe2+ 
B)  Cu2+ 
C)  Mg2+ 
D)  Zn2+ 
A)  Fe2+ 
B)  Cu2+ 
C)  Mg2+ 
D)  Zn2+

Question 10

An enzyme not involved in the control of glycolysis is

Accepted Answer

A)  hexokinase. 
B)  triose phosphate isomerase. 
C)  pyruvate kinase. 
D)  phosphofructokinase. 
A)  hexokinase. 
B)  triose phosphate isomerase. 
C)  pyruvate kinase. 
D)  phosphofructokinase.

Question 11

Anaerobic metabolism can occur in all these organisms or cells, except :

Accepted Answer

A)  Yeast 
B)  Red blood cells 
C)  Muscle tissue that is working very fast 
D)  Lactobacillus in milk 
E)  Anaerobic metabolism can occur in all of these. 
A)  Yeast 
B)  Red blood cells 
C)  Muscle tissue that is working very fast 
D)  Lactobacillus in milk 
E)  Anaerobic metabolism can occur in all of these.

Question 12

Which of the following is required for substrate-level phosphorylation?

Accepted Answer

A)  The substrate must contain multiple phosphate groups. 
B)  Molecular oxygen must present. 
C)  The standard free energy of the hydrolysis reaction is more negative than that for hydrolysis of the new phosphate compound being formed. 
D)  All of the above are necessary for substrate-level phosphorylation. 
A)  The substrate must contain multiple phosphate groups. 
B)  Molecular oxygen must present. 
C)  The standard free energy of the hydrolysis reaction is more negative than that for hydrolysis of the new phosphate compound being formed. 
D)  All of the above are necessary for substrate-level phosphorylation.

Question 13

What is the relationship between glycolysis and cancer?

Accepted Answer

A)  cancer cells lack a glycolytic pathway 
B)  cancer cells use a modified version of glycolysis 
C)  cancer cells exhibit a much higher level of anaerobic glycolysis than normal cells 
D)  none of these 
A)  cancer cells lack a glycolytic pathway 
B)  cancer cells use a modified version of glycolysis 
C)  cancer cells exhibit a much higher level of anaerobic glycolysis than normal cells 
D)  none of these

Question 14

During glycolysis, ATP is synthesized from ADP and a phosphate group transferred from an acid anhydride.

Accepted Answer

A) True 
 B)False

Question 15

The fate of pyruvate produced during glycolysis depends primarily on the availability of

Accepted Answer

A)  NAD+ to keep the pathway going. 
B)  molecular oxygen. 
C)  ADP for conversion to ATP. 
D)  coenzyme A for further metabolism of pyruvate. 
E)  phosphoric acid for the synthesis of ATP. 
A)  NAD+ to keep the pathway going. 
B)  molecular oxygen. 
C)  ADP for conversion to ATP. 
D)  coenzyme A for further metabolism of pyruvate. 
E)  phosphoric acid for the synthesis of ATP.

Question 16

Enolase catalyzes

Accepted Answer

A)  the cleavage of fructose bis phosphate into two 3-carbon units. 
B)  the dehydration of 2-phosphoglycerate. 
C)  the conversion of phosphoenolpyruvate to pyruvate. 
D)  the conversion of glucose-6-phosphate to fructose-6-phosphate. 
A)  the cleavage of fructose bis phosphate into two 3-carbon units. 
B)  the dehydration of 2-phosphoglycerate. 
C)  the conversion of phosphoenolpyruvate to pyruvate. 
D)  the conversion of glucose-6-phosphate to fructose-6-phosphate.

Question 17

Which of the following glycolytic enzymes forms a mixed anhydride from phosphoric acid?

Accepted Answer

A)  hexokinase. 
B)  phosphofructokinase. 
C)  glyceraldehyde-3-phosphate dehydrogenase. 
D)  phosphoglycerate kinase. 
E)  pyruvate kinase. 
A)  hexokinase. 
B)  phosphofructokinase. 
C)  glyceraldehyde-3-phosphate dehydrogenase. 
D)  phosphoglycerate kinase. 
E)  pyruvate kinase.

Question 18

Which of the following terms describes an enzyme that transfers a phosphate group from ATP to a substrate?

Accepted Answer

A)  kinase 
B)  isomerase 
C)  mutase 
D)  dehydrogenase 
A)  kinase 
B)  isomerase 
C)  mutase 
D)  dehydrogenase

Question 19

The equilibrium for isomerization of dihydroxyacetone phosphate to glyceraldehyde-3-phosphate is favored because

Accepted Answer

A)  the standard free energy is negative 
B)  glyceraldehyde-3-phosphate is being continuously drained off for the subsequent reaction in the glycolytic pathway 
C)  the value of the equilibrium constant favors the reaction 
D)  it is driven by the hydrolysis of ATP 
A)  the standard free energy is negative 
B)  glyceraldehyde-3-phosphate is being continuously drained off for the subsequent reaction in the glycolytic pathway 
C)  the value of the equilibrium constant favors the reaction 
D)  it is driven by the hydrolysis of ATP

Question 20

The phosphorylation of glucose to glucose 6-phosphate

Accepted Answer

A)  is so strongly exergonic that it does not require a catalyst. 
B)  is an exergonic reaction not coupled to any other reaction. 
C)  is an endergonic reaction that takes place because it is coupled to the exergonic hydrolysis of ATP. 
D)  is an exergonic reaction that is coupled to the endergonic hydrolysis of ATP. 
A)  is so strongly exergonic that it does not require a catalyst. 
B)  is an exergonic reaction not coupled to any other reaction. 
C)  is an endergonic reaction that takes place because it is coupled to the exergonic hydrolysis of ATP. 
D)  is an exergonic reaction that is coupled to the endergonic hydrolysis of ATP.

Exam 17: Glycolysis

Methanol is extremely toxic, but not directly. In the body, it is converted into formaldehyde; that's what's actually the poison. What kind of enzyme catalyses this conversion?

How many enzymes of glycolysis are control points for the pathway?

The binding of glucose to hexokinase

Glycolysis

​ Phosphorylation of fructose 6-phosphate to produce fructose-1,6- bis phosphate happens in the _____ step of glycolysis.

Consider the following information: How many molecules of ATP might theoretically have been produced when coupled to the conversion of one molecule phosphoenolpyruvate to pyruvate?

In humans, pyruvate can be converted to

Which of the following enzymes forms a thioester using a cysteine residue as a key intermediate?

During glycolysis, enolase , the enzyme that catalyzes the conversion of 2-phophoglycerate to phosphoenolpyruvate requires _____ as a cofactor.

An enzyme not involved in the control of glycolysis is

Anaerobic metabolism can occur in all these organisms or cells, except :

Which of the following is required for substrate-level phosphorylation?

What is the relationship between glycolysis and cancer?

During glycolysis, ATP is synthesized from ADP and a phosphate group transferred from an acid anhydride.

The fate of pyruvate produced during glycolysis depends primarily on the availability of

Enolase catalyzes

Which of the following glycolytic enzymes forms a mixed anhydride from phosphoric acid?

Which of the following terms describes an enzyme that transfers a phosphate group from ATP to a substrate?

The equilibrium for isomerization of dihydroxyacetone phosphate to glyceraldehyde-3-phosphate is favored because

The phosphorylation of glucose to glucose 6-phosphate

Biochemistry and the Organization of Cells

Water the Solvent for Biochemical Reactions

Amino Acids and Peptides

The Three Dimensional Structure of Proteins

Protein Purification and Characterization Techniques

The Behavior of Proteins Enzymes

The Behavior of Proteins Enzymes Mechanisms and Control

Lipids and Proteins Are Associated in Biological Membranes

Nucleic Acids How Structure Conveys Information

Biosynthesis of Nucleic Acids Replication

Transcription of the Genetic Code the Biosynthesis of Rna

Protein Synthesis Translation of the Genetic Message

Nucleic Acid Biotechnology Techniques

Viruses Cancer and Immunology

The Importance of Energy Changes and Electron Transfer in Metabolism

Carbohydrates

Storage Mechanisms and Control in Carbohydrate Metabolism

The Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Lipid Metabolism

Photosynthesis

The Metabolism of Nitrogen

Integration of Metabolism Cellular Signaling

Filters

Phosphorylation of fructose 6-phosphate to produce fructose-1,6- bis phosphate happens in the _____ step of glycolysis.