Correct Solutions.
1. Pyruvate dehydrogenase kinase catalyzes a reaction that results in which of
the following?
The phosphorylation and inactivation of E1 subunit (pyruvate dehydrogenase complex
1. Which of the following intermediates is an allosteric activator of pyruvate
kinase?
a. Fructose 1.6 bisphosphate
1. Which of the following is the initial second messenger in the signaling cascade
initiated by glucagon?
a. cAMP
1. Hereditary fructose intolerance in caused by a deficiency in aldolase B. These
individuals may present with hypoglycemia due to an accumulation of fructose 1-
P in the cell and inhibition of which of the following pathways?
a. Gluconeogenesis and glycogenolysis
1. Following insulin binding its receptor and autophosphorylation of the beta
chain, what is the initial step in the cascade of events?
a. Recruitment of the insulin receptor substrate
1. What sequence of enzymes allows for the synthesis of glycogen from glucose
6-P?
Phosphoglucomutase, UDP-glucose phosphorylase, glycogen synthase amylo-
(1,4a1,6)-transglycosylase
1. Complex II, succinate dehydrogenase, is not considered to be part of the
process of oxidative phosphorylation because it is unable to do which of the
following activities?
a. Pump protons from the mitochondrial matrix to the intermembrane space
1. Which of the following is the primary GLUT transporter in skeletal muscle and
adipose tissue?
GLUT 4
1. Which of the following best describes the net effect of the 8 steps of the TCA
cycle?
a. This process completely oxidizes an acetyl group to carbon dioxide
1. Which of the following enzymes is correctly paired with this activator?
a. Pyruvate dehydrogenase complex, pyruvate
1. ATP is a high energy molecule that is often hydrolyzed during reactions. The
energy within ATP is stored primarily in which of the following compounds of the
molecule?
a. In the high energy phosphate bonds
1. Which of the following is a key inhibitor of the a-ketoglutarate dehydrogenase?
NADH
1. As electrons flow through complexes in the inner mitochondrial membrane,
protons are pumped from the matrix to the intermembrane space. Which of the
following statements is most reflective of the pH in the intermembrane space?
a. The pH is higher in the matrix when compared to the intermembrane space
, 1. Pyruvate dehydrogenase complex is highly regulated. The enzyme will be most
active when which of the following compounds is high?
Pyruvate
1. TCA cycle intermediates are always being removed for various metabolic
processes. One example of this is the removal of succinyl CoA which is used for
the synthesis of which of the following compounds?
Heme
1. The fully reduced quinol form of CoQ contains which of the following
combinations of electrons and protons?
2 e- and two protons
1. Individuals with a deficiency in glucose 6-P dehydrogenase often present with
hemolytic anemia. This is primarily due to a deficiency in which of the following
metabolic products?
NADPH
1. Within the red blood cell, glucose can be oxidized to which of the following
products?
lactate and ribose 5- phosphate
1. Which of the following is an inhibitor of isocitrate dehydrogenase and a-
ketoglutarate dehydrogenase?
a. NADH
1. The non-oxidative stage of the pentose phosphate pathway produces
substances that are intermediates of ____?
Glycolysis
1. The glycerol 3-P shuttle is the major shuttle of most tissues. Which of the
following best describes the transfer of electrons by this shuttle?
a. Electrons are directly transferred from glycerol 3-P to an FAD containing glycerol
phosphate dehydrogenase
1. Glycogen degradation in the liver can be enhanced by the activation of alpha-
adrenergic receptors by epinephrine. The initial step in this cascade involves
which of the following second messengers or active enzymes?
a. Phospholipase C
1. Which of the following enzymes is involved in the non-oxidative portion of the
pentose pathway?
Transketolase
1. Heme can inhibit its own synthesis by inhibiting the activity of which of the
following enzymes?
a. Aminolevulinic acid synthase
1. Under low energy conditions, AMP will bind to phosphofructokinase-1 and
glycogen phosphorylase. This is an example of which of the following types of
enzyme regulation?
a. Allosteric activation
1. Activation of glycogen phosphorylase is regulated in several manners. In
skeletal muscle, which of the following compounds can allosterically activate the
enzyme?
a. AMP