Final Exam Review UNE medical biochemistry Questions
& Answers Rated 100% Correct!!
Under fasting conditions (ratio of insulin: glucagon <1), elevated glucagon will
activate which of the following enzymes?
hormone sensitive lipase
Ketonuria, hypoglycemia, and severe acidosis are prime diagnostic indicators of
the presentation of type 1 diabetic ketoacidosis. Which of the following
compounds are "ketone bodies" that would be elevated in serum of urine of a
patient in this condition?
D-3-hydroxybutyrate and acetoacetate
What is the purpose of cholesterol esterification within the cell? (the conversion
of cholesterol to cholesteryl ester)
a. this modification makes cholesterol more soluble in the plasma membrane
b. this modification does not change the chemical properties of cholesterol
c. esterification is the first step in the synthesis of cortisol
d. esterification traps cholesterol in the cell
esterification traps cholesterol in the cell
An individual goes to bed around 8 pm and doesn't wake up until 9 am the next
morning. During this time, which of the following is the primary oxidizable
substrate in the skeletal muscle?
a. free fatty acids
b. glycogen
c. amino acids
d. lactate
free fatty acids
A 22-year-old woman engaging in a political protest goes on a hunger strike on a
prominent corner in a city park. She refuses all offers of food for except for water
through the first 2 weeks. Under these conditions there is a decreased reliance on
which of the following pathways for fuel?
a. β-oxidation
b. ketogenesis
c. gluconeogenesis
d. lipolysis
gluconeogenesis
In reverse cholesterol transport HDL interacts with the ABCA1 transporter to
move cholesterol from the cell to the HDL. This also requires the activity of which
of the following enzyme?
a. lipoprotein lipase
b. cholesteryl ester transfer protein (CETP)
c. lecithin cholesterol acyltransferase (LCAT)
d. LDL receptor
lecithin cholesterol acyltransferase (LCAT)
A 16-year-old woman presents to her primary care physician for a follow up visit.
At her initial visit, 3 months ago, her serum cholesterol was 255 mg/dL (above
, normal). She finds this very disappointing as she started a strict dietary regime
reducing all fats and cholesterol, replacing them with a high carbohydrate diet.
You tell her that high carbohydrate diets can increase serum triglyceride levels in
some individuals. This can be attributed in an increase in the synthesis of which
of the following lipoproteins?
a. chylomicrons
b. VLDL
c. IDL
d. HDL
e. LDL
VLDL
a 5-year-old presents to her primary care physician. Her mother is concerned due
to persistent diarrhea which is worse when eating fatty foods. The child also has
some clinical signs of a deficiency in fat-soluble vitamins. Based on this
information the child likely has a deficiency in the ability to synthesize which of
the following lipoproteins?
a. chylomicrons
b. VLDLs
c. LDLs
d. HDLs
chylomicrons
The interaction of chylomicorns with lipoprotein lipase is stimulated by which of
the following Apo proteins?
a. ApoB 100
b. Apo B 48
c. Apo C II
d. Apo E
Apo C II
A defect in the thioesterase subunit of fatty acid synthase would impair which of
the following activities of the enzyme complex?
a. liberation of newly assembled palmitate from the enzyme
b. priming of the enzyme iwth acetyl-CoA
c. Liberation of Co2 from 3-ketoacyl synthase
d. binding of malonyl-CoA to an SH group
liberation of newly assembled palmitate from the enzyme
An increase in the ratio of insulin to glucagon leads to which of the following
metabolic shifts?
a. acetyl-CoA carboxylase will become dephosphorylated and active
b. cytosolic levels of malonyl-CoA will decrease
c. hormone sensitive lipase will become dephosphorylated and active
d. VLDL synthesis will decrease
acetyl-CoA carboxylase will become dephosphorylated and active
HDL particles interact with VLDL particles to exchange cholesterol ester for
triacylglyerols. Which of the following enzymes is responsible for this process?
a. cholesterol ester transfer protein (CETP)
b. LCAT (lecithin cholesterol acyltransferase)
& Answers Rated 100% Correct!!
Under fasting conditions (ratio of insulin: glucagon <1), elevated glucagon will
activate which of the following enzymes?
hormone sensitive lipase
Ketonuria, hypoglycemia, and severe acidosis are prime diagnostic indicators of
the presentation of type 1 diabetic ketoacidosis. Which of the following
compounds are "ketone bodies" that would be elevated in serum of urine of a
patient in this condition?
D-3-hydroxybutyrate and acetoacetate
What is the purpose of cholesterol esterification within the cell? (the conversion
of cholesterol to cholesteryl ester)
a. this modification makes cholesterol more soluble in the plasma membrane
b. this modification does not change the chemical properties of cholesterol
c. esterification is the first step in the synthesis of cortisol
d. esterification traps cholesterol in the cell
esterification traps cholesterol in the cell
An individual goes to bed around 8 pm and doesn't wake up until 9 am the next
morning. During this time, which of the following is the primary oxidizable
substrate in the skeletal muscle?
a. free fatty acids
b. glycogen
c. amino acids
d. lactate
free fatty acids
A 22-year-old woman engaging in a political protest goes on a hunger strike on a
prominent corner in a city park. She refuses all offers of food for except for water
through the first 2 weeks. Under these conditions there is a decreased reliance on
which of the following pathways for fuel?
a. β-oxidation
b. ketogenesis
c. gluconeogenesis
d. lipolysis
gluconeogenesis
In reverse cholesterol transport HDL interacts with the ABCA1 transporter to
move cholesterol from the cell to the HDL. This also requires the activity of which
of the following enzyme?
a. lipoprotein lipase
b. cholesteryl ester transfer protein (CETP)
c. lecithin cholesterol acyltransferase (LCAT)
d. LDL receptor
lecithin cholesterol acyltransferase (LCAT)
A 16-year-old woman presents to her primary care physician for a follow up visit.
At her initial visit, 3 months ago, her serum cholesterol was 255 mg/dL (above
, normal). She finds this very disappointing as she started a strict dietary regime
reducing all fats and cholesterol, replacing them with a high carbohydrate diet.
You tell her that high carbohydrate diets can increase serum triglyceride levels in
some individuals. This can be attributed in an increase in the synthesis of which
of the following lipoproteins?
a. chylomicrons
b. VLDL
c. IDL
d. HDL
e. LDL
VLDL
a 5-year-old presents to her primary care physician. Her mother is concerned due
to persistent diarrhea which is worse when eating fatty foods. The child also has
some clinical signs of a deficiency in fat-soluble vitamins. Based on this
information the child likely has a deficiency in the ability to synthesize which of
the following lipoproteins?
a. chylomicrons
b. VLDLs
c. LDLs
d. HDLs
chylomicrons
The interaction of chylomicorns with lipoprotein lipase is stimulated by which of
the following Apo proteins?
a. ApoB 100
b. Apo B 48
c. Apo C II
d. Apo E
Apo C II
A defect in the thioesterase subunit of fatty acid synthase would impair which of
the following activities of the enzyme complex?
a. liberation of newly assembled palmitate from the enzyme
b. priming of the enzyme iwth acetyl-CoA
c. Liberation of Co2 from 3-ketoacyl synthase
d. binding of malonyl-CoA to an SH group
liberation of newly assembled palmitate from the enzyme
An increase in the ratio of insulin to glucagon leads to which of the following
metabolic shifts?
a. acetyl-CoA carboxylase will become dephosphorylated and active
b. cytosolic levels of malonyl-CoA will decrease
c. hormone sensitive lipase will become dephosphorylated and active
d. VLDL synthesis will decrease
acetyl-CoA carboxylase will become dephosphorylated and active
HDL particles interact with VLDL particles to exchange cholesterol ester for
triacylglyerols. Which of the following enzymes is responsible for this process?
a. cholesterol ester transfer protein (CETP)
b. LCAT (lecithin cholesterol acyltransferase)
