Question 1

The benefit of measuring the initial rate of a reaction V0 is that at the beginning of a reaction:

Accepted Answer

A) [ES] can be measured accurately. 
B) changes in [S] are negligible,so [S] can be treated as a constant. 
C) changes in Km are negligible,so Km can be treated as a constant. 
D) V0 = Vmax. 
E) varying [S] has no effect on V0. 
A) [ES] can be measured accurately. 
B) changes in [S] are negligible,so [S] can be treated as a constant. 
C) changes in Km are negligible,so Km can be treated as a constant. 
D) V0 = Vmax. 
E) varying [S] has no effect on V0.

Question 2

Which one of the following statements is true of enzyme catalysts?

Accepted Answer

A) Their catalytic activity is independent of pH. 
B) They are generally equally active on D and L isomers of a given substrate. 
C) They can increase the equilibrium constant for a given reaction by a thousand fold or more. 
D) They can increase the reaction rate for a given reaction by a thousand-fold or more. 
E) To be effective,they must be present at the same concentration as their substrate. 
A) Their catalytic activity is independent of pH. 
B) They are generally equally active on D and L isomers of a given substrate. 
C) They can increase the equilibrium constant for a given reaction by a thousand fold or more. 
D) They can increase the reaction rate for a given reaction by a thousand-fold or more. 
E) To be effective,they must be present at the same concentration as their substrate.

Question 3

Enzyme X exhibits maximum activity at pH = 6.9.X shows a fairly sharp decrease in its activity when the pH goes much lower than 6.4.One likely interpretation of this pH activity is that:

Accepted Answer

A) a Glu residue on the enzyme is involved in the reaction. 
B) a His residue on the enzyme is involved in the reaction. 
C) the enzyme has a metallic cofactor. 
D) the enzyme is found in gastric secretions. 
E) the reaction relies on specific acid-base catalysis. 
A) a Glu residue on the enzyme is involved in the reaction. 
B) a His residue on the enzyme is involved in the reaction. 
C) the enzyme has a metallic cofactor. 
D) the enzyme is found in gastric secretions. 
E) the reaction relies on specific acid-base catalysis.

Question 4

What is the difference between general acid-base catalysis and specific acid-base catalysis? (Assume that the solvent is water. )

Accepted Answer

Specific acid-base catalysis refers to c

Question 5

Enzymes differ from other catalysts in that only enzymes:

Accepted Answer

A) are not consumed in the reaction. 
B) display specificity toward a single reactant. 
C) fail to influence the equilibrium point of the reaction. 
D) form an activated complex with the reactants. 
E) lower the activation energy of the reaction catalyzed. 
A) are not consumed in the reaction. 
B) display specificity toward a single reactant. 
C) fail to influence the equilibrium point of the reaction. 
D) form an activated complex with the reactants. 
E) lower the activation energy of the reaction catalyzed.

Question 6

Methanol (wood alcohol)is highly toxic because it is converted to formaldehyde in a reaction catalyzed by the enzyme alcohol dehydrogenase:
NAD+ + methanol $\rightarrow$ NADH + H+ + formaldehyde
Part of the medical treatment for methanol poisoning is to administer ethanol (ethyl alcohol)in amounts large enough to cause intoxication under normal circumstances.Explain this in terms of what you know about examples of enzymatic reactions.

Accepted Answer

Ethanol is a structural analog of methan

Question 7

Explain how a biochemist might discover that a certain enzyme is allosterically regulated.

Accepted Answer

The enzyme would show kinetics that do n

The benefit of measuring the initial rate of a reaction V₀ is that at the beginning of a reaction:

Which one of the following statements is true of enzyme catalysts?

Enzyme X exhibits maximum activity at pH = 6.9.X shows a fairly sharp decrease in its activity when the pH goes much lower than 6.4.One likely interpretation of this pH activity is that:

What is the difference between general acid-base catalysis and specific acid-base catalysis? (Assume that the solvent is water. )

Enzymes differ from other catalysts in that only enzymes:

Explain how a biochemist might discover that a certain enzyme is allosterically regulated.

The Foundations of Biochemistry

Water

Amino Acids, peptides, and Proteins

The Three-Dimensional Structure of Proteins

Protein Function

Carbohydrates and Glycobiology

Nucleotides and Nucleic Acids

Recombinant Dna Technology

Lipids

Biological Membranes and Transport

Biosignaling

Principles of Bioenergetics

Glycolysis, gluconeogenesis, and the Pentose Phosphate Pathway

Principles of Metabolic Regulation

The Citric Acid Cycle

Fatty Acid Catabolism

Amino Acid Oxidation and the Production of Urea

Oxidative Phosphorylation and Photophosphorylation

Carbohydrate Biosynthesis in Plants and Bacteria

Lipid Biosynthesis

Biosynthesis of Amino Acids, nucleotides, and Related Molecules

Integration and Hormonal Regulation of Mammalian Metabolism

Genes and Chromosomes

Dna Metabolism

Rna Metabolism

Protein Metabolism

Regulation of Gene Expression

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Exam 6: Enzymes

The benefit of measuring the initial rate of a reaction V0 is that at the beginning of a reaction:

Which one of the following statements is true of enzyme catalysts?

Enzyme X exhibits maximum activity at pH = 6.9.X shows a fairly sharp decrease in its activity when the pH goes much lower than 6.4.One likely interpretation of this pH activity is that:

What is the difference between general acid-base catalysis and specific acid-base catalysis? (Assume that the solvent is water. )

Enzymes differ from other catalysts in that only enzymes:

Explain how a biochemist might discover that a certain enzyme is allosterically regulated.

The Foundations of Biochemistry

Water

Amino Acids, peptides, and Proteins

The Three-Dimensional Structure of Proteins

Protein Function

Carbohydrates and Glycobiology

Nucleotides and Nucleic Acids

Recombinant Dna Technology

Lipids

Biological Membranes and Transport

Biosignaling

Principles of Bioenergetics

Glycolysis, gluconeogenesis, and the Pentose Phosphate Pathway

Principles of Metabolic Regulation

The Citric Acid Cycle

Fatty Acid Catabolism

Amino Acid Oxidation and the Production of Urea

Oxidative Phosphorylation and Photophosphorylation

Carbohydrate Biosynthesis in Plants and Bacteria

Lipid Biosynthesis

Biosynthesis of Amino Acids, nucleotides, and Related Molecules

Integration and Hormonal Regulation of Mammalian Metabolism

Genes and Chromosomes

Dna Metabolism

Rna Metabolism

Protein Metabolism

Regulation of Gene Expression

Filters

The benefit of measuring the initial rate of a reaction V₀ is that at the beginning of a reaction: