Question 1

In the Lineweaver-Burk double reciprocal plot the horizontal intercept is equal to __________.

Accepted Answer

A)   1/[S]
B)   1/V
C)   Km/Vmax
D)   1/Vmax
E)   -1/KmF) B) and E)
G) A) and E)

Question 2

Catalase has a Km of 25 mM and a kcat of 4×107sec-1 with H2O2 as a substrate. Carbonic anhydrase has a Km of 26mM and a kcat of 4×105 sec-1. What does this data tell you about these two enzymes?

Accepted Answer

Catalase has a higher affinity...

Question 3

What is a proenzyme ?

Accepted Answer

A proenzyme is the inactive precursor of an enzyme.

Question 4

Describe the term coenzyme. Give two examples.

Accepted Answer

A coenzyme is a small organic molecule required in the catalytic mechanism of a certain enzyme. Examples include NAD⁺ and FAD.

Question 5

Which of the following is not an important metal in biological systems?

Accepted Answer

A)   Na+
B)   K+
C)   Mg++
D)   Cu++
E)   Ba++F) A) and E)
G) C) and E)

Question 6

The main enzyme used to detoxify alcohol in humans is __________.

Accepted Answer

A)   ADH1
B)   ADH2
C)   ADH3
D)   ADH4
E)   All of the above are correct.F) A) and B)
G) A) and C)

Question 7

Is a reaction mechanism altered by the presence of a catalyst? Explain.

Accepted Answer

Catalysts do alter the reaction mechanis...

Question 8

Explain the difference between the energy of reaction and energy of activation.

Accepted Answer

The energy of a reaction is th...

Question 9

In the Lineweaver-Burk double reciprocal plot the vertical intercept is equal to __________.

Accepted Answer

A)   1/[S]
B)   1/V
C)   Km/Vmax
D)   1/Vmax
E)   -1/KmF) All of the above
G) A) and E)

Question 10

What is a noncompetitive inhibitor?

Accepted Answer

A noncompetitive inhibitor is ...

Question 11

Which of the following amino acids can participate in covalent catalysis?

Accepted Answer

A)   Tryptophan
B)   Alanine
C)   Serine
D)   Histidine
E)   Both C and D are correct.F) B) and C)
G) A) and E)

Question 12

Consider the following reaction diagram. Which letter indicates the transition state?

Accepted Answer

A)   A
B)   B
C)   C
D)   D
E)   EF) C) and D)
G) B) and E)

Question 13

The table represents a specific substrate concentrations for an enzyme that displays classical Michaelis-Menten kinetics. Two sets of inhibitor data are also included. Determine the Km and Vmax for the uninhibited enzyme.
 $\begin{array}{l} 
\quad\quad\quad\quad\quad\text { Without } \quad\quad\quad\quad\quad\quad\quad\quad {\mathrm{V}_{\mathrm{o}}(\mathrm{mM} / \mathrm{s})} \
\begin{array}{llcc} 
{[\mathrm{S}](\mathrm{mM})} & \text { Inhibitor } & \text { With Inhibitor A } & \text { With Inhibitor B } \
1.3 & 2.50 & 1.17 & 0.62 \
2.6 & 4.00 & 2.10 & 1.42 \
6.5 & 6.30 & 4.00 & 2.65 \
13.0 & 7.60 & 5.70 & 3.12 \
26.0 & 9.00 & 7.20 & 3.58
\end{array}
\end{array}$

Accepted Answer

V_max= 10 μm/s K_m= 5 μm
...

Question 14

Pyruvate carboxylase is an example of which class of enzymes?

Accepted Answer

A)   Oxidoreductase
B)   Transferase
C)   Hydrolase
D)   Ligase
E)   LyaseF) A) and E)
G) None of the above

Question 15

In the Lineweaver-Burk double reciprocal plot the slope is equal to __________.

Accepted Answer

A)   1/[S]
B)   1/V
C)   Km/Vmax
D)   1/Vmax
E)   -1/KmF) None of the above
G) A) and B)

Question 16

Positive cooperativity is a feature of what type of enzymatic control?

Accepted Answer

A)   Genetic control
B)   Covalent modification
C)   Allosteric regulation
D)   Compartmentation
E)   Both B and C are correct.F) A) and B)
G) C) and D)

Question 17

In addition to serine and aspartate which of the following amino acids is a member of the serine triad?

Accepted Answer

A)   Threonine
B)   Tyrosine
C)   Glutamine
D)   Histidine
E)   GlycineF) B) and C)
G) A) and B) D

Question 18

Consider the following diagram. What constitutes the activation energy for the forward reaction?

Accepted Answer

A)   C-A
B)   C-E
C)   E-A
D)   C-B
E)   E-DF) B) and E)
G) C) and D)

Question 19

Which of the following is not present in the active site of alcohol dehydrogenase?

Accepted Answer

A)   Zn++
B)   Histidine
C)   Cysteine
D)   NAD+
E)   ProlineF) None of the above
G) C) and E)

Question 20

Which of the following is not an assumption of the law of mass action?

Accepted Answer

A)   Forward reaction is linear.
B)   Reverse reaction is linear.
C)   System is homogenous.
D)   Interacting molecules move randomly and independently of each other.
E)   All are assumptions of the law of mass action.F) D) and E)
G) A) and E)

Exam 6: Enzymes

In the Lineweaver-Burk double reciprocal plot the horizontal intercept is equal to __________.

Correct Answer
verified

Catalase has a K_m of 25 mM and a k_cat of 4×10⁷sec^-1 with H₂O₂ as a substrate. Carbonic anhydrase has a K_m of 26mM and a k_ca_t of 4×10⁵ sec^-1. What does this data tell you about these two enzymes?

Correct Answer
verified
Catalase has a higher affinity...
View Answer

What is a proenzyme ?

Correct Answer
verified
A proenzyme is the inactive precursor of an enzyme.

Describe the term coenzyme. Give two examples.

Correct Answer
verified
A coenzyme is a small organic molecule required in the catalytic mechanism of a certain enzyme. Examples include NAD⁺ and FAD.

Which of the following is not an important metal in biological systems?

Correct Answer
verified

The main enzyme used to detoxify alcohol in humans is __________.

Correct Answer
verified

Is a reaction mechanism altered by the presence of a catalyst? Explain.

Correct Answer
verified
Catalysts do alter the reaction mechanis...
View Answer

Explain the difference between the energy of reaction and energy of activation.

Correct Answer
verified
The energy of a reaction is th...
View Answer

In the Lineweaver-Burk double reciprocal plot the vertical intercept is equal to __________.

Correct Answer
verified

What is a noncompetitive inhibitor?

Correct Answer
verified
A noncompetitive inhibitor is ...
View Answer

Which of the following amino acids can participate in covalent catalysis?

Correct Answer
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Consider the following reaction diagram. Which letter indicates the transition state?

Correct Answer
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Correct Answer
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V_max= 10 μm/s K_m= 5 μm
...
View Answer

Pyruvate carboxylase is an example of which class of enzymes?

Correct Answer
verified

In the Lineweaver-Burk double reciprocal plot the slope is equal to __________.

Correct Answer
verified

Positive cooperativity is a feature of what type of enzymatic control?

Correct Answer
verified

In addition to serine and aspartate which of the following amino acids is a member of the serine triad?

Correct Answer
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D

Consider the following diagram. What constitutes the activation energy for the forward reaction?

Correct Answer
verified

Which of the following is not present in the active site of alcohol dehydrogenase?

Correct Answer
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Which of the following is not an assumption of the law of mass action?

Correct Answer
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Exam 6: Enzymes

In the Lineweaver-Burk double reciprocal plot the horizontal intercept is equal to __________.

Correct AnswerverifiedShow Answer

Catalase has a Km of 25 mM and a kcat of 4×107sec-1 with H2O2 as a substrate. Carbonic anhydrase has a Km of 26mM and a kcat of 4×105 sec-1. What does this data tell you about these two enzymes?

Correct AnswerverifiedCatalase has a higher affinity...View AnswerShow Answer

What is a proenzyme ?

Correct AnswerverifiedA proenzyme is the inactive precursor of an enzyme.

Describe the term coenzyme. Give two examples.

Correct AnswerverifiedA coenzyme is a small organic molecule required in the catalytic mechanism of a certain enzyme. Examples include NAD+ and FAD.

Which of the following is not an important metal in biological systems?

Correct AnswerverifiedShow Answer

The main enzyme used to detoxify alcohol in humans is __________.

Correct AnswerverifiedShow Answer

Is a reaction mechanism altered by the presence of a catalyst? Explain.

Correct AnswerverifiedCatalysts do alter the reaction mechanis...View AnswerShow Answer

Explain the difference between the energy of reaction and energy of activation.

Correct AnswerverifiedThe energy of a reaction is th...View AnswerShow Answer

In the Lineweaver-Burk double reciprocal plot the vertical intercept is equal to __________.

Correct AnswerverifiedShow Answer

What is a noncompetitive inhibitor?

Correct AnswerverifiedA noncompetitive inhibitor is ...View AnswerShow Answer

Which of the following amino acids can participate in covalent catalysis?

Correct AnswerverifiedShow Answer

Consider the following reaction diagram. Which letter indicates the transition state?

Correct AnswerverifiedShow Answer

Correct AnswerverifiedVmax = 10 μm/s Km = 5 μm ...View AnswerShow Answer

Pyruvate carboxylase is an example of which class of enzymes?

Correct AnswerverifiedShow Answer

In the Lineweaver-Burk double reciprocal plot the slope is equal to __________.

Correct AnswerverifiedShow Answer

Positive cooperativity is a feature of what type of enzymatic control?

Correct AnswerverifiedShow Answer

In addition to serine and aspartate which of the following amino acids is a member of the serine triad?

Correct AnswerverifiedD

Consider the following diagram. What constitutes the activation energy for the forward reaction?

Correct AnswerverifiedShow Answer

Which of the following is not present in the active site of alcohol dehydrogenase?

Correct AnswerverifiedShow Answer

Which of the following is not an assumption of the law of mass action?

Correct AnswerverifiedShow Answer

Correct Answer
verified

Catalase has a K_m of 25 mM and a k_cat of 4×10⁷sec^-1 with H₂O₂ as a substrate. Carbonic anhydrase has a K_m of 26mM and a k_ca_t of 4×10⁵ sec^-1. What does this data tell you about these two enzymes?

Correct Answer
verified
Catalase has a higher affinity...
View Answer

Correct Answer
verified
A proenzyme is the inactive precursor of an enzyme.

Correct Answer
verified
A coenzyme is a small organic molecule required in the catalytic mechanism of a certain enzyme. Examples include NAD⁺ and FAD.

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
Catalysts do alter the reaction mechanis...
View Answer

Correct Answer
verified
The energy of a reaction is th...
View Answer

Correct Answer
verified

Correct Answer
verified
A noncompetitive inhibitor is ...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
V_max= 10 μm/s K_m= 5 μm
...
View Answer

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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D

Correct Answer
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Correct Answer
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Correct Answer
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