BCH 361 TESTED QUESTIONS WITH REVISED ANSWERS

BCH 361 TESTED QUESTIONS WITH
REVISED ANSWERS

What enzyme is activated by direct association with an active G protein? - Answer-*A)
adenylate cyclase*
C) protein kinase A
B) cAMP phosphodiesterase D) protein kinase G

Activity of the Ras protein is analogous to the in terms of its ability to bind
GTP. - Answer-*A) G protein α subunit*
C) G protein γ subunit
B) G protein β subunit
D) calmodulin

Which of the following metabolic pathways is carried out only in the liver? - Answer-A)
glycogen storage
D) triacylglycerol synthesis
*B) ketogenesis*
E) pentose phosphate pathway
C) fatty acid synthesis

Fatty acid oxidation occurs in the ; fatty acid synthesis occurs in the .-
Answer-*A) mitochondria; cytosol*
B) mitochondria; lysosome
C) lysosome; Golgi apparatus
D) cytosol; Golgi apparatus
E) mitochondria; endoplasmic reticulum

Acetyl-CoA carboxylase requires the coenzyme and as an energy
source. - Answer-A) FADH2; acyl-CoA hydrolysis
B) NADPH; GTP
*C) biotin; ATP*
D) coenzyme A; GTP
E) thiamine pyrophosphate; acyl-CoA hydrolysis

Which of the following pathways supplies NADPH needed for fatty acid
synthesis in mammals? - Answer-A) citric acid cycle C) glycolysis
*B) pentose phosphate pathway*
D) light reactions of photosynthesis

Which enzyme is the most important control point for fatty acid synthesis? - Answer-A)
ATP-citrate lyase
D) 3-hydroxyacyl-ACP dehydrase
B) transacylase
*E) acetyl-CoA carboxylase*
C) 3-ketoacyl-ACP reductase

, The conversion of 3-hydroxybutyrate to two molecules of acetyl-CoA produces 1
NADH and consumes 1 equivalent of ATP. What is the net ATP yield from the
complete oxidation of 3-hydroxybutyrate? - Answer-A) 1.5
B) 11.5
C) 13.5
*D) 21.5*
E) 23.5



Which of the following metabolic pathways occurs exclusively in the cytosol? - Answer-
A) citric acid cycle C) fatty acid oxidation
B) ketogenesis
*D) fatty acid synthesis*

Which of the following pathways is active in the muscle only during the well-fed
state? - Answer-A) glycolysis
*D) glycogen storage*
B) fatty acid oxidation
E) ketone body synthesis
C) fatty acid synthesis

Which of the following enzymes is inhibited as a result of insulin binding to its
receptor? - Answer-A) glycogen synthase
D) pyruvate dehydrogenase
B) pyruvate kinase *E) fructose-1,6-bisphosphatase*
C) acetyl-CoA carboxylase

The effect of epinephrine upon the liver is most similar to the effect of which of
the following hormones? - Answer-A) insulin
C) leptin
*B) glucagon*
D) cortisol

Which of the following best explains the chain of events that occurs when
glucagon binds to its receptor? - Answer-A) activation of protein kinase A, activation of
G protein, activation of adenylate
cyclase, production of cAMP
B) activation of adenylate cyclase, production of cAMP, activation of protein
kinase A, activation of G protein
C) production of cAMP, activation of adenylate cyclase, activation of protein
kinase A, activation of G protein
D) activation of G protein, activation of protein kinase A, activation of adenylate
cyclase, production of cAMP
*E) activation of G protein, activation of adenylate cyclase, production of cAMP,
activation of protein kinase A*

After several days of fasting, the liver begins producing relatively large amounts
of ketone bodies. Which type of tissue is highly dependent upon this as its sole
source of energy in the absence of glucose? - Answer-A) heart