UNE BIOCHEMISTRY UPDATED EXAM SCRIPT QUESTIONS
AND ANSWERS GUARANTEE A+
✔✔A patient recently diagnosed with colon cancer is being treated with 5-fluorouracil.
Which of the following enzymes will this drug directly inhibit? - ✔✔Thymidylate synthase
✔✔An elevation of purine nucleotides will negatively regulate pyrimidine synthesis
through which of the following mechanisms? - ✔✔Inhibiting the activity of carbamoyl
phosphate synthetase II
✔✔Purine biosynthesis starts with the activation of a 5-carbon sugar. In this initial
reaction, ribose 5-phosphate is converted into which of the following compounds? -
✔✔PRPP (5- phosphoribosylpyrophosphate)
✔✔A 40-year-old male comes in to the doctor's office with severe pain in his big toe. He
is diagnosed with gout. Allopurinol is administered and this drug will inhibit which of the
following enzymes? - ✔✔Xanthine oxidase
✔✔In the salvage of purines, hypoxanthine-guanine phosphoribosyl transferase
(HGPRT) is responsible for which of the following processes? - ✔✔Conversion of
guanine to guanosine monophosphate (GMP)
✔✔In the case of a deficiency of biotin, which of the following enzymes required for fatty
acid metabolism will be impaired? - ✔✔Acetyl-CoA carboxylase
✔✔During fatty acid synthesis, after the initial step involving acetyl-CoA, the fatty acid
chain is elongated by the addition of which of the following compounds? - ✔✔Malonyl-
CoA
✔✔Which of the following compounds or substrates is required for the synthesis of
tyrosine? (+ indicates the compound is required; - indicates the compound is not
required) - ✔✔4
✔✔A 2-day-old infant test positive for hyperphenylalaninemia. This is most likely caused
by a heritable defect in which of the following enzymes? - ✔✔Phenylalanine
hydroxylase
✔✔You and a friend are being chased by a bear. Under these conditions levels of
epinephrine are increased due to metabolism of which of the following amino acids? -
✔✔Tyrosine
✔✔In pyrimidine synthesis, uridine triphosphate (UTP) can feedback and inhibit which
of the following enzymes? - ✔✔Carbamoyl phosphate synthase II
,✔✔Which of the following characteristics distinguish most RNA molecules from DNA? -
✔✔Uridine base on RNA, whereas a thymidine base on DNA
✔✔Which of the following lipoproteins distributes dietary lipids? - ✔✔Chylomicron
✔✔The interaction fo chylomicrons with lipoprotein lipase is stimulated by which of the
following App proteins? - ✔✔ApoCII
✔✔Nascent chylomicrons are synthesized in which tissue? - ✔✔Intestine
✔✔Bile salts are synthesized from cholesterol and are used for the emulsification of
dietary lipids. What is the primary fate of bile salts during digestion? - ✔✔They are
reabsorbed in the ileum
✔✔Nascent chylomicrons interact with HDL particles and obtain which fo the following
Apo proteins? - ✔✔ApoCII and ApoE
✔✔The activity of pancreatic lipase is inhibited by which of the following compounds? -
✔✔Bile salts
✔✔Which fo the following statements regarding liid digestion and absorption is true?
A. The products of lipid digestion travel in the circulatory system in the form of micelles.
B. The products of lipid digestion diffuse into capillaries in the vicinity of the intestinal
epithelium.
C. Pancreatic lipase emulsifies lipids.
D. The products of lipid digestion are resynthesizes into triacylglycerols in the intestinal
epithelial cells.
e. In the absence of bile salts, no digestion of lipids would occur. - ✔✔The products of
lipid digestion are resynthesizes into triacylglycerols in intestinal epithelial cells.
✔✔Under fasting conditions, elevated glucagon will activate which of the following
enzymes? - ✔✔Hormone sensitive lipase
✔✔VLDL particles are characterized by which of the following apoproteins? -
✔✔ApoB100
✔✔An increase in insulin leads to which of the following metabolic shifts? - ✔✔Acetyl
CoA carboxylase will become dephosphorylated and active.
✔✔Biotin is a cofactor required for which of the following enzymes? - ✔✔A and B
(Acetyl CoA carboxylase and Pyruvate carboxylase)
, ✔✔The first step in fatty acid synthesis is the formation of ________ from acetyl CoA
and carbon dioxide. - ✔✔Malonyl CoA
✔✔Insulin increases the activity of all of the following enzymes except - ✔✔Hormone
sensitive lipase
✔✔Which fo the following is the regulatory enzyme for fatty acid synthesis? - ✔✔Acetyl
CoA carboxylase
✔✔Which fo the following is the regulated step of fatty acid synthesis in eukaryotes? -
✔✔Carboxylation of acetyl CoA
✔✔Under conditions of starvation, all of the following are true except - ✔✔Malonyl CoA
will be elevated
✔✔Which of the following proteins is responsible for the transfer of ApoB48 to nascent
chylomicrons before secretion into circulation? - ✔✔Microsomal transfer protein (MTP)
✔✔The process of beta-oxidation generated all of the following compounds except -
✔✔NADPH
✔✔During the fasted state, lipolysis is facilitated by the action of hormone sensitive
lipase. This enzyme requires which of the following post - translational modification for
activation? - ✔✔Phosphorylation
✔✔Adiponectin is secreted from adipocytes. One of the primary roles of adiponectin is
to activate the MAPK pathway in skeletal muscle which enhances the activity of which
of the following pathways? - ✔✔Beta-oxidation
✔✔When the process of glucose oxidation is elevated, the acetyl CoA produced will
allosterically activate which of the following enzymes leading to an increase in the
production of oxaloacetate? - ✔✔Pyruvate carboxylase
✔✔The process of ketogenesis refers to the conversion of acetyl CoA to which of the
following compounds? - ✔✔Beta-hydroxybutyrate
✔✔The transport of newly-synthesized fatty acids to the adipose requires all fo the
following except - ✔✔Carnitine to shuttle the fatty acids out of the mitochondria
✔✔In the case of deficiency of biotin, which of the following enzymes required for fatty
acid synthesis will be impaired? - ✔✔Acetyl CoA carboxylase
AND ANSWERS GUARANTEE A+
✔✔A patient recently diagnosed with colon cancer is being treated with 5-fluorouracil.
Which of the following enzymes will this drug directly inhibit? - ✔✔Thymidylate synthase
✔✔An elevation of purine nucleotides will negatively regulate pyrimidine synthesis
through which of the following mechanisms? - ✔✔Inhibiting the activity of carbamoyl
phosphate synthetase II
✔✔Purine biosynthesis starts with the activation of a 5-carbon sugar. In this initial
reaction, ribose 5-phosphate is converted into which of the following compounds? -
✔✔PRPP (5- phosphoribosylpyrophosphate)
✔✔A 40-year-old male comes in to the doctor's office with severe pain in his big toe. He
is diagnosed with gout. Allopurinol is administered and this drug will inhibit which of the
following enzymes? - ✔✔Xanthine oxidase
✔✔In the salvage of purines, hypoxanthine-guanine phosphoribosyl transferase
(HGPRT) is responsible for which of the following processes? - ✔✔Conversion of
guanine to guanosine monophosphate (GMP)
✔✔In the case of a deficiency of biotin, which of the following enzymes required for fatty
acid metabolism will be impaired? - ✔✔Acetyl-CoA carboxylase
✔✔During fatty acid synthesis, after the initial step involving acetyl-CoA, the fatty acid
chain is elongated by the addition of which of the following compounds? - ✔✔Malonyl-
CoA
✔✔Which of the following compounds or substrates is required for the synthesis of
tyrosine? (+ indicates the compound is required; - indicates the compound is not
required) - ✔✔4
✔✔A 2-day-old infant test positive for hyperphenylalaninemia. This is most likely caused
by a heritable defect in which of the following enzymes? - ✔✔Phenylalanine
hydroxylase
✔✔You and a friend are being chased by a bear. Under these conditions levels of
epinephrine are increased due to metabolism of which of the following amino acids? -
✔✔Tyrosine
✔✔In pyrimidine synthesis, uridine triphosphate (UTP) can feedback and inhibit which
of the following enzymes? - ✔✔Carbamoyl phosphate synthase II
,✔✔Which of the following characteristics distinguish most RNA molecules from DNA? -
✔✔Uridine base on RNA, whereas a thymidine base on DNA
✔✔Which of the following lipoproteins distributes dietary lipids? - ✔✔Chylomicron
✔✔The interaction fo chylomicrons with lipoprotein lipase is stimulated by which of the
following App proteins? - ✔✔ApoCII
✔✔Nascent chylomicrons are synthesized in which tissue? - ✔✔Intestine
✔✔Bile salts are synthesized from cholesterol and are used for the emulsification of
dietary lipids. What is the primary fate of bile salts during digestion? - ✔✔They are
reabsorbed in the ileum
✔✔Nascent chylomicrons interact with HDL particles and obtain which fo the following
Apo proteins? - ✔✔ApoCII and ApoE
✔✔The activity of pancreatic lipase is inhibited by which of the following compounds? -
✔✔Bile salts
✔✔Which fo the following statements regarding liid digestion and absorption is true?
A. The products of lipid digestion travel in the circulatory system in the form of micelles.
B. The products of lipid digestion diffuse into capillaries in the vicinity of the intestinal
epithelium.
C. Pancreatic lipase emulsifies lipids.
D. The products of lipid digestion are resynthesizes into triacylglycerols in the intestinal
epithelial cells.
e. In the absence of bile salts, no digestion of lipids would occur. - ✔✔The products of
lipid digestion are resynthesizes into triacylglycerols in intestinal epithelial cells.
✔✔Under fasting conditions, elevated glucagon will activate which of the following
enzymes? - ✔✔Hormone sensitive lipase
✔✔VLDL particles are characterized by which of the following apoproteins? -
✔✔ApoB100
✔✔An increase in insulin leads to which of the following metabolic shifts? - ✔✔Acetyl
CoA carboxylase will become dephosphorylated and active.
✔✔Biotin is a cofactor required for which of the following enzymes? - ✔✔A and B
(Acetyl CoA carboxylase and Pyruvate carboxylase)
, ✔✔The first step in fatty acid synthesis is the formation of ________ from acetyl CoA
and carbon dioxide. - ✔✔Malonyl CoA
✔✔Insulin increases the activity of all of the following enzymes except - ✔✔Hormone
sensitive lipase
✔✔Which fo the following is the regulatory enzyme for fatty acid synthesis? - ✔✔Acetyl
CoA carboxylase
✔✔Which fo the following is the regulated step of fatty acid synthesis in eukaryotes? -
✔✔Carboxylation of acetyl CoA
✔✔Under conditions of starvation, all of the following are true except - ✔✔Malonyl CoA
will be elevated
✔✔Which of the following proteins is responsible for the transfer of ApoB48 to nascent
chylomicrons before secretion into circulation? - ✔✔Microsomal transfer protein (MTP)
✔✔The process of beta-oxidation generated all of the following compounds except -
✔✔NADPH
✔✔During the fasted state, lipolysis is facilitated by the action of hormone sensitive
lipase. This enzyme requires which of the following post - translational modification for
activation? - ✔✔Phosphorylation
✔✔Adiponectin is secreted from adipocytes. One of the primary roles of adiponectin is
to activate the MAPK pathway in skeletal muscle which enhances the activity of which
of the following pathways? - ✔✔Beta-oxidation
✔✔When the process of glucose oxidation is elevated, the acetyl CoA produced will
allosterically activate which of the following enzymes leading to an increase in the
production of oxaloacetate? - ✔✔Pyruvate carboxylase
✔✔The process of ketogenesis refers to the conversion of acetyl CoA to which of the
following compounds? - ✔✔Beta-hydroxybutyrate
✔✔The transport of newly-synthesized fatty acids to the adipose requires all fo the
following except - ✔✔Carnitine to shuttle the fatty acids out of the mitochondria
✔✔In the case of deficiency of biotin, which of the following enzymes required for fatty
acid synthesis will be impaired? - ✔✔Acetyl CoA carboxylase
