BCH 367 CH-7 UPDATED EXAM QUESTIONS
AND CORRECT ANSWERS
When an enzyme is operating at Vmax, the enzyme:
a) displays zero-order kinetics.
b) displays second-order kinetics.
c) displays pseudo—first-order kinetics.
d) displays kinetics dependent upon the number of reactants specific to that enzyme system.
e) displays first-order kinetics. - CORRECT ANSWERS a
Enzymes that follow simple Michaelis-Menten kinetics are called Michaelis-Menten enzymes.
Alternatively, enzymes that regulate the flux of biochemical through metabolic pathways are
called _____ enzymes. - CORRECT ANSWERS allosteric
Which of the following is a CORRECT unit for a second-order rate constant?
a) M/s
b)M_1
c)M_1 s_1
d)M/s_1
e) M - CORRECT ANSWERS c
Allosteric enzymes are _____, where _____ at one site _____.
a) isozymes; the activity; is different from the activity at a different site
, b) isozymes; activity; affects the activity at a different site
c) cooperative; proteolytic cleavage; increases the activity of the enzyme
d) cooperative; activity; affects the activity at a different site
e) cooperative; inhibition; increases the ability of another site to bind substrate. - CORRECT
ANSWERS d
The Michaelis constant, KM:
a) is equal to ½Vmax.
b) is equal to the velocity of the reaction when the enzyme is 50% saturated with substrate.
c) is equal to the substrate concentration when the velocity of the reaction is 50% of the
maximum velocity.
d) is equal to the rate constant, k, when the reaction is in the steady state. - CORRECT
ANSWERS c
Which of the following statements about allosteric enzymes is true?
a) Allosteric enzymes follow Michaelis-Menten kinetics.
b) Allosteric enzymes can exist in an R state, which has a low affinity for substrate.
c) Allosteric enzymes have quaternary structure.
d) Allosteric enzymes capture the binding energy of the substrate to catalyze otherwise
thermodynamically unfavorable reactions. - CORRECT ANSWERS c
In a pseudo —first-order reaction:
a) a second-order reaction appears to be a first-order reaction.
b) a first-order reaction appears to be a second-order reaction.
AND CORRECT ANSWERS
When an enzyme is operating at Vmax, the enzyme:
a) displays zero-order kinetics.
b) displays second-order kinetics.
c) displays pseudo—first-order kinetics.
d) displays kinetics dependent upon the number of reactants specific to that enzyme system.
e) displays first-order kinetics. - CORRECT ANSWERS a
Enzymes that follow simple Michaelis-Menten kinetics are called Michaelis-Menten enzymes.
Alternatively, enzymes that regulate the flux of biochemical through metabolic pathways are
called _____ enzymes. - CORRECT ANSWERS allosteric
Which of the following is a CORRECT unit for a second-order rate constant?
a) M/s
b)M_1
c)M_1 s_1
d)M/s_1
e) M - CORRECT ANSWERS c
Allosteric enzymes are _____, where _____ at one site _____.
a) isozymes; the activity; is different from the activity at a different site
, b) isozymes; activity; affects the activity at a different site
c) cooperative; proteolytic cleavage; increases the activity of the enzyme
d) cooperative; activity; affects the activity at a different site
e) cooperative; inhibition; increases the ability of another site to bind substrate. - CORRECT
ANSWERS d
The Michaelis constant, KM:
a) is equal to ½Vmax.
b) is equal to the velocity of the reaction when the enzyme is 50% saturated with substrate.
c) is equal to the substrate concentration when the velocity of the reaction is 50% of the
maximum velocity.
d) is equal to the rate constant, k, when the reaction is in the steady state. - CORRECT
ANSWERS c
Which of the following statements about allosteric enzymes is true?
a) Allosteric enzymes follow Michaelis-Menten kinetics.
b) Allosteric enzymes can exist in an R state, which has a low affinity for substrate.
c) Allosteric enzymes have quaternary structure.
d) Allosteric enzymes capture the binding energy of the substrate to catalyze otherwise
thermodynamically unfavorable reactions. - CORRECT ANSWERS c
In a pseudo —first-order reaction:
a) a second-order reaction appears to be a first-order reaction.
b) a first-order reaction appears to be a second-order reaction.
