UNE Biochemistry Midterm Study (Questions from weekly
evaluations) With Complete Solutions
A 19-year-old boy is diagnosed with Creutzfeldt-Jakob disease
which is caused by the introduction of an amyloid fold in the
disease-causing protein. The introduction of this fold causes the
protein to transition from a primarily alpha helical structure to
an aggregate of mostly beta sheets. This change in protein
structure (leading to disease) is best attributed to changes in
which of the following? correct answer: folding of the
secondary structures
Which of the following is the best description of primary protein
structure? correct answer: a newly synthesized strand of amino
acids
How do most enzymes reduce the activation energy needed to
move a reaction forward? correct answer: providing an active
site most complementary the transition state
Movement of ammonia from an amino acid to an a-keto acid
involves a family of enzymes best categorized as which of the
following? correct answer: transferases
Hemoglobin has the ability to display cooperative binding while
myoglobin does not display this binding kinetic pattern. Which
of the following differences between the two proteins accounts
for this difference in binding kinetics? correct answer: the
presence of quaternary structure
, Changes in the physiological variables listed below can alter the
affinity of hemoglobin for oxygen. Which of the following will
lower the affinity of hemoglobin for oxygen? correct answer:
increase in 2,3 bisphosphoglycerate (BPG)
An enzyme has a mutation within the substrate binding site that
reduces the binding of the coenzyme needed for covalent
catalysis. Which of the following is likely to result as a
consequence of this mutation? correct answer: the enzyme will
not be able to form the transition state complex
Chymotrypsin is a protease that cleaves peptide bonds. It is
characterized as which of the following classes of enzymes?
correct answer: hydrolases
If a mutation is made within the active site of an enzyme
resulting in a decrease in Km, which of the following will be
true with respect to the enzyme kinetics? correct answer: the
enzyme will require a lower substrate concentration to reach 1/2
Vmax
Which of the following best describes an enzyme inhibitor that
increases the Km but does not change the Vmax? correct
answer: a competitive inhibitor
An enzyme is participating in a general acid-base catalysis
reaction with an optimal reaction pH of 6.0. If acid is added to
the environment reducing the pH to 3, what is the Iikely impact
to the rate of the reaction? correct answer: the rate of the
reaction is likely to decrease as the pH is out of optimal catalytic
range
evaluations) With Complete Solutions
A 19-year-old boy is diagnosed with Creutzfeldt-Jakob disease
which is caused by the introduction of an amyloid fold in the
disease-causing protein. The introduction of this fold causes the
protein to transition from a primarily alpha helical structure to
an aggregate of mostly beta sheets. This change in protein
structure (leading to disease) is best attributed to changes in
which of the following? correct answer: folding of the
secondary structures
Which of the following is the best description of primary protein
structure? correct answer: a newly synthesized strand of amino
acids
How do most enzymes reduce the activation energy needed to
move a reaction forward? correct answer: providing an active
site most complementary the transition state
Movement of ammonia from an amino acid to an a-keto acid
involves a family of enzymes best categorized as which of the
following? correct answer: transferases
Hemoglobin has the ability to display cooperative binding while
myoglobin does not display this binding kinetic pattern. Which
of the following differences between the two proteins accounts
for this difference in binding kinetics? correct answer: the
presence of quaternary structure
, Changes in the physiological variables listed below can alter the
affinity of hemoglobin for oxygen. Which of the following will
lower the affinity of hemoglobin for oxygen? correct answer:
increase in 2,3 bisphosphoglycerate (BPG)
An enzyme has a mutation within the substrate binding site that
reduces the binding of the coenzyme needed for covalent
catalysis. Which of the following is likely to result as a
consequence of this mutation? correct answer: the enzyme will
not be able to form the transition state complex
Chymotrypsin is a protease that cleaves peptide bonds. It is
characterized as which of the following classes of enzymes?
correct answer: hydrolases
If a mutation is made within the active site of an enzyme
resulting in a decrease in Km, which of the following will be
true with respect to the enzyme kinetics? correct answer: the
enzyme will require a lower substrate concentration to reach 1/2
Vmax
Which of the following best describes an enzyme inhibitor that
increases the Km but does not change the Vmax? correct
answer: a competitive inhibitor
An enzyme is participating in a general acid-base catalysis
reaction with an optimal reaction pH of 6.0. If acid is added to
the environment reducing the pH to 3, what is the Iikely impact
to the rate of the reaction? correct answer: the rate of the
reaction is likely to decrease as the pH is out of optimal catalytic
range
