Deck 15: Glucose Catabolism

Question 1

The enzyme _____forms a Schiff base upon formation of the enzyme-substrate complex allowing aspartate mediated cleavage of the substrate.

A)hexokinase
B)phosphoglucose isomerase
C)glucose-6-phosphatase
D)phosphoglucose mutase
E)aldolase

Answer 1

aldolase

Question 2

Matching
Choose the correct answer from the list.Not all the answers will be used.

Vitamin B₁ is a component of the coenzyme ______ essential for development of an electron sink necessary for decarboxylation of pyruvate.

A) fructose-1,6-bisphosphatase
B) pentose phosphate
C) pyruvate decarboxylase
D) hypoglycemia
E) phosphofructokinase
F) NADP⁺
G) thiamine pyrophosphate
H) ATP
I) galactosemia
J) NAD⁺
K) fluoride ion
L) pyruvate
M) glucogenic
N) FAD

Answer 2

thiamine pyrophosphate

Question 3

Glycolytic synthesis of ATP occurs via

A)oxidation.
B)reduction.
C)substrate-level phosphorylation.
D)oxidative phosphorylation.
E)photophosphorylation.

Answer 3

substrate-level phosphorylation.

Question 4

Glucose is converted to ______ in skeletal muscle under anaerobic conditions.

A)lactate
B)acetyaldehyde
C)fructose
D)glycogen
E)acetyl-CoA

Question 5

Experimental evidence indicates that glyceraldehyde-3-phosphate dehydrogenase contains a critical ______ residue in its active site,as shown by its inactivation by iodoacetamide.

A)alanine
B)aspartate
C)cysteine
D)methionine
E)lysine

Question 6

Matching
Choose the correct answer from the list.Not all the answers will be used.

NADPH used in lipid biosynthesis is produced by the ______ pathway.

A) fructose-1,6-bisphosphatase
B) pentose phosphate
C) pyruvate decarboxylase
D) hypoglycemia
E) phosphofructokinase
F) NADP⁺
G) thiamine pyrophosphate
H) ATP
I) galactosemia
J) NAD⁺
K) fluoride ion
L) pyruvate
M) glucogenic
N) FAD

Question 7

Matching
Choose the correct answer from the list.Not all the answers will be used.

______ is an inhibitor of enolase which was useful in elucidating the glycolytic pathway.

A) fructose-1,6-bisphosphatase
B) pentose phosphate
C) pyruvate decarboxylase
D) hypoglycemia
E) phosphofructokinase
F) NADP⁺
G) thiamine pyrophosphate
H) ATP
I) galactosemia
J) NAD⁺
K) fluoride ion
L) pyruvate
M) glucogenic
N) FAD

Question 8

Phosphofructokinase is allosterically _____ by high concentrations of _____.
(I)activated;ATP
(II)inhibited;ATP
(III)inhibited;fructose-2,6-bisphosphate
(IV)activated;fructose -2,6-bisphosphate

A)I,III
B)II,III
C)II,IV
D)I,IV
E)none of the above

Question 9

Matching
Choose the correct answer from the list.Not all the answers will be used.

The products of glycolysis include: ATP,NADH,and ______.

A) fructose-1,6-bisphosphatase
B) pentose phosphate
C) pyruvate decarboxylase
D) hypoglycemia
E) phosphofructokinase
F) NADP⁺
G) thiamine pyrophosphate
H) ATP
I) galactosemia
J) NAD⁺
K) fluoride ion
L) pyruvate
M) glucogenic
N) FAD

Question 10

Matching
Choose the correct answer from the list.Not all the answers will be used.

A genetic deficiency of a single transferase enzyme required for sugar group exchange causes the medical condition known as _____ which results in failure to thrive,mental retardation,and potential liver damage.

A) fructose-1,6-bisphosphatase
B) pentose phosphate
C) pyruvate decarboxylase
D) hypoglycemia
E) phosphofructokinase
F) NADP⁺
G) thiamine pyrophosphate
H) ATP
I) galactosemia
J) NAD⁺
K) fluoride ion
L) pyruvate
M) glucogenic
N) FAD

Question 11

Matching
Choose the correct answer from the list.Not all the answers will be used.

The enzyme _____ participates in a regulatory substrate cycle along with phosphofructokinase.

A) fructose-1,6-bisphosphatase
B) pentose phosphate
C) pyruvate decarboxylase
D) hypoglycemia
E) phosphofructokinase
F) NADP⁺
G) thiamine pyrophosphate
H) ATP
I) galactosemia
J) NAD⁺
K) fluoride ion
L) pyruvate
M) glucogenic
N) FAD

Question 12

Matching
Choose the correct answer from the list.Not all the answers will be used.

The coenzyme ______ is the oxidizing agent in both aerobic and anaerobic glycolysis.

A) fructose-1,6-bisphosphatase
B) pentose phosphate
C) pyruvate decarboxylase
D) hypoglycemia
E) phosphofructokinase
F) NADP⁺
G) thiamine pyrophosphate
H) ATP
I) galactosemia
J) NAD⁺
K) fluoride ion
L) pyruvate
M) glucogenic
N) FAD

Question 13

Matching
Choose the correct answer from the list.Not all the answers will be used.

Glycolysis forms ____ under either aerobic or anaerobic conditions.

A) fructose-1,6-bisphosphatase
B) pentose phosphate
C) pyruvate decarboxylase
D) hypoglycemia
E) phosphofructokinase
F) NADP⁺
G) thiamine pyrophosphate
H) ATP
I) galactosemia
J) NAD⁺
K) fluoride ion
L) pyruvate
M) glucogenic
N) FAD

Question 14

Aerobic glycolysis produces a net yield of ______ ATP.

A)1
B)2
C)3
D)4
E)more than 4

Question 15

In alcoholic fermentation,acetaldehyde is produced by

A)the decarboxylation of pyruvate.
B)the carboxylation of pyruvate.
C)the decarboxylation of lactate.
D)the carboxylation of lactate.
E)none of the above

Question 16

The metabolism of mannose requires _____ to produce ____ for entry into the glycolytic pathway.

A)hexokinase;glucose-6-phosphate
B)hexokinase;fructose-6-phosphate
C)phosphomannose isomerase;glucose-6-phosphate
D)phosphomannose isomerase;fructose-6-phosphate
E)phosphofructokinase;bisphosphoglycerate

Question 17

Which of the following enzymes catalyzes the transfer of a phosphoryl group from ATP to glucose?

A)hexokinase
B)phosphoglucose isomerase
C)glucose-6-phosphatase
D)phosphoglucose mutase
E)A transfer such as this does not occur in glycolysis.

Question 18

Matching
Choose the correct answer from the list.Not all the answers will be used.

The enzyme _____ is the major control point for glycolysis in muscle.

A) fructose-1,6-bisphosphatase
B) pentose phosphate
C) pyruvate decarboxylase
D) hypoglycemia
E) phosphofructokinase
F) NADP⁺
G) thiamine pyrophosphate
H) ATP
I) galactosemia
J) NAD⁺
K) fluoride ion
L) pyruvate
M) glucogenic
N) FAD

Question 19

Matching
Choose the correct answer from the list.Not all the answers will be used.

The enzyme ______ ,which catalyzes the formation of acetyaldehyde and CO₂ from pyruvate,is not present in animals.

A) fructose-1,6-bisphosphatase
B) pentose phosphate
C) pyruvate decarboxylase
D) hypoglycemia
E) phosphofructokinase
F) NADP⁺
G) thiamine pyrophosphate
H) ATP
I) galactosemia
J) NAD⁺
K) fluoride ion
L) pyruvate
M) glucogenic
N) FAD

Question 20

The enzymes that catalyze glycolysis are located in the

A)endoplasmic reticulum.
B)mitochondrial matrix.
C)cytosol.
D)inner mitochondrial membrane.
E)outer mitochondrial membrane.

Question 21

Which of the following reactions does not occur in mammals?

A)pyruvate + NADH → lactate + NAD⁺
B)ribulose-5-phosphoate → ribose-5-phosphate
C)mannose + ATP → mannose-6-phosphate + ADP + P_i
D)6-phophogluconate + NADP⁺ → ribulose-5-phosphate + NADPH + CO₂
E)pyruvate + NADH + H⁺ → CO₂ + ethanol + NAD⁺

Question 22

Conversion of galactose to glucose
(I)requires an epimerase.
(II)requires uridine diphosphate.
(III)requires a transferase
(IV)requires an isomerase.

A)I,II,III,IV
B)I,II,III
C)II,III,IV
D)II,III
E)I,III

Question 23

The reaction below is catalyzed by yeast alcohol dehydrogenase.Which of the following corresponds to X and Y in this reaction?

A)X = NADH⁺ Y = NAD + H⁺
B)X = NAD⁺ Y = NADH + H⁺
C)X = NADH + H⁺ Y = NAD⁺
D)X = NAD + H⁺ Y = NADH⁺
E)X = NADPH + H⁺ Y = NADP⁺

Question 24

Which glycolytic enzyme catalyzes a reaction with an enediolate intermediate?

A)phosphoglucomutase
B)triose phosphate isomerase
C)phosphofructokinase
D)aldolase
E)none of the above

Question 25

Consider the following portion of the glycolytic sequence catalyzed by the enzymes above the arrows.Which products(s)will produce ATP?

A)I,IV
B)II,IV
C)II only
D)III,IV
E)IV only

Question 26

The reaction catalyzed by the enzyme aldolase has a $\Delta$ G˚' ≈ +23 kJ/mol.In muscle cells,the reaction proceeds in this same,forward direction.How can this occur?

A)This $\Delta$ G˚' means it is thermodynamically favored.
B)The enzyme changes the ∆G of the reaction in cells to something favorable.
C)The concentration of reactant(s)must be significantly greater than product(s)in cells.
D)The concentration of product(s)must be significantly greater than reactant(s)in cells.
E)none of the above

Question 27

Which of the following compounds contains a "high-energy" bond and is used to produce ATP by substrate-level phosphorylation in glycolysis?

A)

B)

C)

D)

E)

Question 28

In which of the following metabolic conversions is ATP required during glycolysis?
(I)fructose-6-phosphate SYMBOL 174 \f "Symbol" fructose-1,6-bisphosphate
(II)glucose SYMBOL 174 \f "Symbol" glucose-6-phosphate
(III)fructose-1,6-bisphosphate SYMBOL 174 \f "Symbol" dihydroxyacetone phosphate + glyceraldehyde-3-phosphate
(IV)glucose-6-phosphate SYMBOL 174 \f "Symbol" fructose-6-phosphate

A)I only
B)II only
C)I,II
D)I,III
E)I,IV

Question 29

Which enzyme has an intermediate of the form presented below?

A)phosphofructokinase
B)aldolase
C)pyruvate decarboxylase
D)glyceraldehyde-3-phosphate dehydrogenase
E)triose phosphate isomerase

Question 30

In skeletal muscle cells,oxidation of NADH generated from anaerobic glycolysis occurs during which of the following reactions?

A)acetaldehyde SYMBOL 174 \f "Symbol" ethanol
B)lactate SYMBOL 174 \f "Symbol" pyruvate
C)phosphoenolpyruvate SYMBOL 174 \f "Symbol" pyruvate
D)pyruvate SYMBOL 174 \f "Symbol" lactate
E)glyceraldehyde-3-phosphate SYMBOL 174 \f "Symbol" 1,3-bisphosphoglycerate

Question 31

Which of the following best explains why an enzyme hasn't evolved to catalyze the following reaction as the first step of glycolysis?
Glucose + P_i -> glucose-6-phosphate
(I)The use of ATP is required for this step to serve as a regulatory control point.
(II)The use of ATP is important because it helps keep its concentration low.Otherwise the high [ATP] would slow glycolysis too much through feedback inhibition.
(III)The large positive $\Delta$ G˚' of this reaction would need to be overcome by an exceedingly high [P_i].
(IV)Inorganic phosphate cannot be specifically placed on the carbon in the 6^th position.

A)I,III
B)I,II
C)II,IV
D)I only
E)III only

Question 32

Methanol is highly toxic,not because of its own activity,but because it is converted metabolically into formaldehyde,which is the actual poison.What enzyme catalyzes this conversion?

A)methanol caboxylase
B)methanol transferase
C)alcohol transmutase
D)alcohol carboxylase
E)alcohol dehydrogenase

Question 33

Which enzyme is involved in substrate level phosphorylation in glycolysis?

A)Hexokinase
B)√Pyruvate kinase
C)Glyceraldehyde-3phosphate dehydrogenase
D)Aldolase
E)None of the above.

Question 34

Which of the following best describes the entry of mannose into glycolysis?

A)hydrolyzed into two glucose units,they enter normally
B)phosphorylated at C-1;UMP moiety transferred from UDP-glucose;epimerized at C-2;released from UMP moiety on next transfer as G1P
C)phosphorylated at C-1;UMP moiety transferred from UDP-glucose;epimerized at C-4;released from UMP moiety on next transfer as G1P
D)phosphorylated at C-6;epimerized at C-2 to produce G6P
E)phosphorylated at C-6;isomerized to produce F6P

Question 35

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

A)fructose-1,6-bisphosphate $\to$ dihydroxyacetone phosphate + glyceraldehyde-3-phosphate
B)glucose $\to$ glucose-6-phosphate
C)2-phosphoglyerate $\to$ phosphoenolpyruvate
D)fructose-6-phosphate $\to$ fructose-1,6-bisphosphate
E)phosphoenolpyruvate $\to$ pyruvate

Question 36

If glucose labeled at the C-1 position with ¹⁴C passes through glycolysis,on which carbon of pyruvate will the radiolabel be found?

A)1
B)2
C)3
D)It will be released in CO₂ rather than present in pyruvate.
E)Not enough information is given to predict.

Question 37

Individuals with galactosemia

A)cannot catabolize galactose via glycolysis.
B)lack the enzyme hexokinase which is required for phosphorylation of galactose.
C)lack the enzyme galactokinase which is required for interconversion between glucose-1-phosphate and galactose-1-phosphate.
D)cannot synthesize galactose from glucose.
E)lack adequate uridine diphosphosphate.

Question 38

Which of the following is true regarding glycolysis?
(I)There is a net oxidation of substrate carbon atoms.
(II)There is no net release of free energy.
(III)Pyruvate is generated only during aerobic glycolysis.
(IV)There is 2 ATP formed for every 2 glucose molecules.
)

A)I only
B)I,IV
C)I,III,IV
D)IV only
E)II,IV

Question 39

Which is the net equation for aerobic glycolysis?

A)Glucose + 2 ATP SYMBOL 174 \f "Symbol" 2 lactate + 2 ADP + 2 P_i
B)Glucose + 2 ADP + 2 P_i + 2 NAD⁺ SYMBOL 174 \f "Symbol" 2 pyruvate + 2 ATP + 2 NADH + + 2 H₂O 4 H⁺
C)Glucose + 2 ADP + 2 P_i SYMBOL 174 \f "Symbol" 2 lactate + 4 ATP + 4 H⁺
D)Glucose + 2 ATP + 2 NAD⁺SYMBOL 174 \f "Symbol" 2 pyruvate + 4 ATP + 4 NADH + 4 H⁺
E)Glucose + 2 ADP + 2 P_i + 2 NAD⁺SYMBOL 174 \f "Symbol" 2 lactate + 4 ATP + 2 NADH + 4 H⁺

Question 40

During glycolysis,the steps between glucose and formation of the triose phosphates collectively

A)consume two ATP and two NADH molecules.
B)consume two ATP molecules.
C)produce two ADP and two NADH molecules.
D)produce two ATP and two NAD⁺ molecules.
E)consume two NAD⁺ molecules.

Question 41

Which reaction above is an oxidation reaction?

A)I,III
B)II,III
C)III only
D)IV only
E)None of the reactions I-V is oxidation reactions.

Question 42

Which of the following best describes the control exhibited by phosphofructokinase (PFK)?

A)It is allosterically inhibited by ATP and citrate.
B)It is allosterically activated by F2,6P.
C)It is allosterically activated by ATP and citrate.
D)Both A and B are correct.
E)Both B and C are correct.

Question 43

During reactions utilizing the enzymes shown below,in which case(s)is ATP produced?
(I)phosphofructokinase (PFK)
(II)phosphoglycerate kinase (PGK)
(III)pyruvate kinase (PK)

A)I
B)II
C)III
D)I,II
E)II,III

Question 44

In which reaction above is ATP required?

A)I,II
B)II only
C)III only
D)IV,V
E)None of the reactions I-V requires ATP.

Question 45

The utilization of fructose in glycolysis in the liver

A)requires UDP-glucose.
B)requires one extra ATP.
C)uses GTP rather than ATP.
D)bypasses phosphofructokinase (PFK)regulation.
E)enters glycolysis as fructose bisphosphate (FBP).

Question 46

Select the enzyme from the list which would catalyze the reaction shown below.

A)hexokinase (HK)
B)pyruvate kinease (PK)
C)enolase
D)phosphoglucomutase (PGM)
E)G3P dehydrogenase (G3PDH)

Question 47

In which reaction above is at least 1 NADH formed?

A)II only
B)III only
C)IV only
D)IV,V
E)None of the reaction I-V form NADH.

Question 48

ATP

A)inhibits activity of phosphofructokinase (PFK)allosterically.
B)activates activity of phosphofructokinase (PFK)allosterically.
C)inhibits activity of phosphofructokinase (PFK)hormonally.
D)activates activity of phosphofructokinase (PFK)hormonally.
E)does not alter phosphofructokinase (PFK)activity.

Question 49

Which of the following is correct regarding the hexose monophosphate shunt?
(I)NADH is generated by the oxidation of glucose-6-phosphate.
(II)Glyceraldehyde-3-phosphate is generated in the reaction.
(III)The pathway requires a transaldolase.
(IV)The pathway generates 3 ATP per 1 glucose-6-phosphate.

A)I,II,III
B)I,II,III,IV
C)II,III,IV
D)II,III
E)III,IV

Question 50

Of the reaction types listed below,which type of reaction is NOT used in glycolysis?

A)oxidation
B)phosphorylation
C)dehydration
D)isomerization
E)All are used in glycolysis.