UNE Medical Biochemistry – Unit 2 Midterm

UNE Medical Biochemistry Unit 2
Midterm Test Exam With 100% Correct
Answers 2026

If unregulated, which of the following pairs of enzymes would
represent a futile cycle? - Correct Answer-Fructose 1,6
bisphosphatase and phosphofructokinase-1


Rotenone blocks complex 1 in the ETC. This increases levels of
NADH and would likely impair the function of which of the
following enzymes? - Correct Answer-Pyruvate
dehydrogenase complex


Newborn screening shows a biotinidase deficiency in a 2-day
old infant. This deficienty impairs the infant's ability to reuse
and recycle biotin. Due to this enzymatic deficiency, the
activity of which of the following enzymes is likely impaired? -
Correct Answer-pyruvate carboxylase


An individual is recently diagnosed with Type 2 diabetes. In
this individual, hyperglycemia may in part be due to inactivity
of which of the following glucose transporters on skeletal
muscle? - Correct Answer-Glut 4 (insulin dependent)



pg. 1 professoraxe
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,The skeletal muscle primarily provides substrate for
gluconeogenesis through which of the following processes? -
Correct Answer-protein catabolism


Alanine can be shuttled from the skeletal muscle to the liver
where it is deaminated to produce pyruvate. When glucagon
is high, pyruvate is primarily used as a substrate for which of
the following pathways? - Correct Answer-gluconeogenesis


Aldolase B facilitaes a reaction that cleaves fructose 1-
phosphate into two 3-carbon molecules that will enter
glycolysis as which of the following compounds? - Correct
Answer-glyceraldehyde-3-phosphate


Within the RBC, NADPH is used for which of the following
processes? - Correct Answer-to re-reduce glutathione


Galactose-1-phosphate is initially converted to glucose-1-
phosphate and requires which of the following compounds? -
Correct Answer-UDP-glucose




pg. 2 professoraxe
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,Which of the following are the two primary products of the
Pentose Phosphate pathway? - Correct Answer-Ribose-5-
phosphate and NADPH


Which of the following enzymes is involved in the non-
oxidative portion of the Pentose Phosphate Pathway? -
Correct Answer-transaldolase


A patient presents with a deficiency of thiamine. If this
patient's liver cells are compared to normal liver cells, which
of the following products would be decreased in the patient's
cells (compared to the normal cells), if the cells are only given
glucose as a fuel? - Correct Answer-CO2 (lack of thiamine
would reduce activity of PDC - as a result, most pyruvate
would be diverted to lactate instead of acetyl-CoA)


Which of the following best describes the net effect of the 8
steps of the TCA cycle? - Correct Answer-The process
completely oxidizes an acetyl group to carbon dioxide


Which of the following compounds allosterically activates
phosphofructokinase-1 (PFK1)? - Correct Answer-fructose 2,6-
bisphosphate




pg. 3 professoraxe
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, Which of the following enzymes is correctly paired with it's
activator? - Correct Answer-pyruvate dehydrogenase;
pyruvate


A newborn male is diagnosed with congenital lactic acidosis
because of a defective electron transport protein. This
deficiency leads to a decrease in the rate at which NADH and
FADH2 can be oxidized to produce ATP via oxidative
phosphorylation and results in an increase in cytosolic AMP.
Under these conditions, which glycolytic enzyme would be
stimulated? - Correct Answer-phosphofructokinase-1 (PFK-1 is
activated by high cytosolic AMP and inhibited by AMP)


Which of the following outlines the order of prosthetic groups
as they are used for catalysis within the PDC? - Correct
Answer-thiamine diphosphate > lipoamide > FAD


Which of the following intermediates of the TCA cycle is
required in the cytosol for fatty acid synthesis? - Correct
Answer-citrate (in the cytosol, citrate is cleaved by citrate
lyase back into oxaloacetate and acetyl CoA)


Which of the following enzymes is responsible for the
degradation of cAMP - Correct Answer-phosphodiesterase


pg. 4 professoraxe
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