UNE Biochemistry Unit 2 Test UPDATED
Questions with CORRECT Answers
3, 2, 4, 1 - CORRECT ANSWER - Order the following statements to illustrate the correct
cascade of events that occurs after ligand binding of G-protein coupled receptor (heptahelical
receptor).
1. Degradation of cAMP by phosphodiesterase
2. Dissociation of Gβ and Gγ subunits
3. G protein exchanges GDP for GTP in the G-αs subunit
4. Activation of adenylyl cyclase (effector E) to generate cAMP
Nuclear localization signal - CORRECT ANSWER - A suspected mutation in the cortisol
receptor is discovered. Cortisol can still bind its receptor but the dimerized complex remains in
the cytosol. Based on this description which region on the receptor is likely impacted?
Free fatty acids - CORRECT ANSWER - What is the primary oxidized fuel for skeletal
muscle in the fasted state?
Glucagon - CORRECT ANSWER - Caffeine is a natural inhibitor of phosphodiesterase. If
you were to consume a large amount of coffee you would likely see a prolonged response to
which of the following stimulants or hormones?
Protein Kinase B - CORRECT ANSWER - In the event that PI-3 kinase is not activated
downstream of insulin, which of the following proteins would not be able to dock to the
membrane?
, Gluconeogenesis - CORRECT ANSWER - A patient is found to have a rare disease in
which the secretory function of the α-cells of the pancreas is impaired. As a consequence,
glucagon cannot be secreted. Direct stimulation of which of the following pathways in liver will
be impaired?
Phosphodiesterase - CORRECT ANSWER - What enzymes is responsible for the
degradation of cAMP?
VLDL particles - CORRECT ANSWER - Insulin stimulates fatty acid synthesis in the
liver. These fatty acids are transported to the adipose tissue as which of the following?
Phosphofructokinase-1 (PFK1) - CORRECT ANSWER - After a meal, fructose 2,6-
bisphosphate levels are elevated. This compound will allosterically activate which of the
following glycolytic enzymes?
Aconitase - CORRECT ANSWER - A farmer finds a cow dead in his field and notices an
unusual plant nearby. Autopsy results show an elevated level of citrate present in the cow's
mitochondria. This data collectively suggest inhibition of which of the following enzymes?
Pyruvate - CORRECT ANSWER - A deficiency in thiamine can reduce the activity of the
pyruvate dehydrogenase complex. Under these conditions, you would expect to have a higher
than normal blood concentration of which of the following metabolites?
Succinate thiokinase - CORRECT ANSWER - A 10-year-old girl is swimming in a local
competition. The intense exercise will increase intracellular calcium levels which in turn will
increase flux through the TCA cycle by stimulating the activity of all of the following enzymes
EXCEPT?
Phosphorylation - CORRECT ANSWER - In order for glucose to be retained within the
cell, which of the following modifications must occur?
Questions with CORRECT Answers
3, 2, 4, 1 - CORRECT ANSWER - Order the following statements to illustrate the correct
cascade of events that occurs after ligand binding of G-protein coupled receptor (heptahelical
receptor).
1. Degradation of cAMP by phosphodiesterase
2. Dissociation of Gβ and Gγ subunits
3. G protein exchanges GDP for GTP in the G-αs subunit
4. Activation of adenylyl cyclase (effector E) to generate cAMP
Nuclear localization signal - CORRECT ANSWER - A suspected mutation in the cortisol
receptor is discovered. Cortisol can still bind its receptor but the dimerized complex remains in
the cytosol. Based on this description which region on the receptor is likely impacted?
Free fatty acids - CORRECT ANSWER - What is the primary oxidized fuel for skeletal
muscle in the fasted state?
Glucagon - CORRECT ANSWER - Caffeine is a natural inhibitor of phosphodiesterase. If
you were to consume a large amount of coffee you would likely see a prolonged response to
which of the following stimulants or hormones?
Protein Kinase B - CORRECT ANSWER - In the event that PI-3 kinase is not activated
downstream of insulin, which of the following proteins would not be able to dock to the
membrane?
, Gluconeogenesis - CORRECT ANSWER - A patient is found to have a rare disease in
which the secretory function of the α-cells of the pancreas is impaired. As a consequence,
glucagon cannot be secreted. Direct stimulation of which of the following pathways in liver will
be impaired?
Phosphodiesterase - CORRECT ANSWER - What enzymes is responsible for the
degradation of cAMP?
VLDL particles - CORRECT ANSWER - Insulin stimulates fatty acid synthesis in the
liver. These fatty acids are transported to the adipose tissue as which of the following?
Phosphofructokinase-1 (PFK1) - CORRECT ANSWER - After a meal, fructose 2,6-
bisphosphate levels are elevated. This compound will allosterically activate which of the
following glycolytic enzymes?
Aconitase - CORRECT ANSWER - A farmer finds a cow dead in his field and notices an
unusual plant nearby. Autopsy results show an elevated level of citrate present in the cow's
mitochondria. This data collectively suggest inhibition of which of the following enzymes?
Pyruvate - CORRECT ANSWER - A deficiency in thiamine can reduce the activity of the
pyruvate dehydrogenase complex. Under these conditions, you would expect to have a higher
than normal blood concentration of which of the following metabolites?
Succinate thiokinase - CORRECT ANSWER - A 10-year-old girl is swimming in a local
competition. The intense exercise will increase intracellular calcium levels which in turn will
increase flux through the TCA cycle by stimulating the activity of all of the following enzymes
EXCEPT?
Phosphorylation - CORRECT ANSWER - In order for glucose to be retained within the
cell, which of the following modifications must occur?
