BCH 369 EXAM 2024 with Questions
Solved 100% Correct | Latest Update
Which of the following would be the first to occur following opening of Ca2+
channels during
acetylcholine-mediated neurotransmission to a muscle cell?
A) reuptake of acetylcholine by the nerve cell
B) release of acetylcholine by the nerve cell
C) binding of SNARE complex to synaptic vesicles and pre-synaptic membrane
D) hydrolysis of acetylcholine by acetylcholinesterase
E) binding of acetylcholine to muscle cell receptors - Answer C) binding of SNARE
complex to synaptic vesicles and pre-synaptic membrane
In the absence of allosteric effectors, the enzyme phosphofructokinase displays
Michaelis-Menten kinetics.The v0/Vmax ratio is 0.9 when the concentration of
its substrate, fructose-6-phosphate, is 0.10
mM. What is the KM for substrate under these conditions?
A) 11 mM B) 22 mM C) 11 µM D) 0.08 µM E) 1.0 mM - Answer C) 11 µM
A galactosyl transferase that catalyzes the reaction below, β3-GalT, has recently been
purified. The reaction velocity was measured in the presence of UDP-[3H]Gal. Use
the graph below to determine the value of KM and Vmax.
, A) KM = 2.27 mM; Vmax = 0.26 µM/h
D) KM = 590 µM; Vmax = 2.27 x 103 µM/h
B) KM = 3.8 mM; Vmax = 0.26 µM/h
E) KM = 590 µM; Vmax = 4.41 x 104 µM/h
C) KM = 3.8 µM; Vmax = 2.27 x 10-3 µM/h - Answer D) KM = 590 µM; Vmax = 2.27 x 103
µM/h
Activation of a G protein in response to hormone binding requires binding of _____ to
the _____
subunit. A) GTP; β B) GDP; γ C) GTP; α D) GDP; α E) GDP; β - Answer C) GTP
All known porins are _____ proteins composed of _____.
A) trimeric; four transmembrane α-helices
D) dimeric; three transmembrane α-helices
B) monomeric; seven transmembrane α-helices
E) trimeric; β-barrels
C) dimeric; β-barrels - Answer E) trimeric; β-barrels
Which of the following must be known to calculate the kcat of an enzyme?
A) The KM for the substrate.
B) Vmax for the substrate, enzyme concentration and KM for the substrate.
C) Vmax for the substrate.
D) Enzyme concentration.
E) Vmax for the substrate and enzyme concentration. - Answer E) Vmax for the
substrate and enzyme concentration.
Solved 100% Correct | Latest Update
Which of the following would be the first to occur following opening of Ca2+
channels during
acetylcholine-mediated neurotransmission to a muscle cell?
A) reuptake of acetylcholine by the nerve cell
B) release of acetylcholine by the nerve cell
C) binding of SNARE complex to synaptic vesicles and pre-synaptic membrane
D) hydrolysis of acetylcholine by acetylcholinesterase
E) binding of acetylcholine to muscle cell receptors - Answer C) binding of SNARE
complex to synaptic vesicles and pre-synaptic membrane
In the absence of allosteric effectors, the enzyme phosphofructokinase displays
Michaelis-Menten kinetics.The v0/Vmax ratio is 0.9 when the concentration of
its substrate, fructose-6-phosphate, is 0.10
mM. What is the KM for substrate under these conditions?
A) 11 mM B) 22 mM C) 11 µM D) 0.08 µM E) 1.0 mM - Answer C) 11 µM
A galactosyl transferase that catalyzes the reaction below, β3-GalT, has recently been
purified. The reaction velocity was measured in the presence of UDP-[3H]Gal. Use
the graph below to determine the value of KM and Vmax.
, A) KM = 2.27 mM; Vmax = 0.26 µM/h
D) KM = 590 µM; Vmax = 2.27 x 103 µM/h
B) KM = 3.8 mM; Vmax = 0.26 µM/h
E) KM = 590 µM; Vmax = 4.41 x 104 µM/h
C) KM = 3.8 µM; Vmax = 2.27 x 10-3 µM/h - Answer D) KM = 590 µM; Vmax = 2.27 x 103
µM/h
Activation of a G protein in response to hormone binding requires binding of _____ to
the _____
subunit. A) GTP; β B) GDP; γ C) GTP; α D) GDP; α E) GDP; β - Answer C) GTP
All known porins are _____ proteins composed of _____.
A) trimeric; four transmembrane α-helices
D) dimeric; three transmembrane α-helices
B) monomeric; seven transmembrane α-helices
E) trimeric; β-barrels
C) dimeric; β-barrels - Answer E) trimeric; β-barrels
Which of the following must be known to calculate the kcat of an enzyme?
A) The KM for the substrate.
B) Vmax for the substrate, enzyme concentration and KM for the substrate.
C) Vmax for the substrate.
D) Enzyme concentration.
E) Vmax for the substrate and enzyme concentration. - Answer E) Vmax for the
substrate and enzyme concentration.
