UPDATED ACTUAL Exam Questions and
CORRECT Answers
Place the following reaction intermediates of the CAC in chronological order
i. malate ii. fumarate iii. succinyl CoA iv. citrate v. a-ketoglutarate - CORRECT
ANSWER - iv, v, iii, ii, i
Oxalosuccinate is a transient intermediate formed during which of the following reactions? -
CORRECT ANSWER - isocitrate to a-ketoglutarate
FADH2 is a product of which of the following reactions? - CORRECT ANSWER -
succinate to fumarate
NADH is produced in which of the following reactions? - CORRECT ANSWER - a-
ketoglutarate to succinyl CoA
Which of the following reactions can be described as anaplerotic? - CORRECT
ANSWER - pyruvate + co2 to oxaloacetate
The enzymes that are unique to the glyoxylate cycle include ____________ - CORRECT
ANSWER - isocitrate lyase
The regulated enzyme of the CAC include _________ - CORRECT ANSWER - a-
ketoglutarate dehydrogenase
The enzymes involved in citrate metabolism include all of the following except ________ -
CORRECT ANSWER - malate synthase
,Redox potential is best defined as - CORRECT ANSWER - the tendency of a species to
gain or lose electrons
In order to determine the standard voltage of a reaction - CORRECT ANSWER - the
standard cells must be written as they occur in the reaction and the voltages are added
Which of the following reactions is an oxidation reaction?
a. NaOH + HCl -> NaCl + H2O
b. CH3COOH -> CH3COO- + H+
c. CH3CHO -> CH3CH2OH
d. CH3CH2OH -> CH3CHO
e. CH2=CH2 + H2O -> CH3CH2OH - CORRECT ANSWER - CH3CH2OH -> CH3CHO
Which of the following reactions has an oxidized product?
a. carboxylic acid -> aldehyde
b. R-SH + R-SH -> R-S-S-R
c. alcohol -> ketone
d. glutamate -> a-ketoglutarate
e. none of the above - CORRECT ANSWER - none of the above
In any redox reaction, an electron donor is - CORRECT ANSWER - the reducing agent
In an redox reaction, an electron acceptor is - CORRECT ANSWER - converted to an
electron donor with the gain of one or more electrons
Each turn of the CAC produces how many moles of CO2? - CORRECT ANSWER -2
Acetyl CoA that is consumed by the CAC is produced from which of the following biochemical
pathways?
,a. glycolysis
b. fatty acid oxidation
c. purine catabolism
d. urea cycle
e. both A and B are correct - CORRECT ANSWER - both A and B are correct
Which of the following is the strongest reducing agent?
a. FADH2 (+ 0.22 V)
b. H2 (+ 0.424 V)
c. cytochrome a * Fe 2+ (-0.29 V)
d. lactate (+0.19 V)
e. H2O (-0.82 V) - CORRECT ANSWER - H2
Which of the following reacts with the acetyl-CoA to form citrate? - CORRECT
ANSWER - oxaloacetate
The redox reaction in which succinate is converted to fumarate uses FAD rather than NAD+
because? - CORRECT ANSWER - FAD is a stronger oxidizing agent than NAD+
Which of the following CAC enzymes are closely regulated?
a. citrate synthase
b. isocitrate dehydrogenase
c. a-ketoglutarate dehydrogenase
d. both A and B are correct
e. A, B, and C are all correct - CORRECT ANSWER - A, B, and C are all correct
Which of the following requires GDP? - CORRECT ANSWER - succinyl-CoA to
succinate
, How many oxidation steps are there in the CAC? - CORRECT ANSWER -4
Which of the following is a cofactor for the conversion of succinate to fumarate? - CORRECT
ANSWER - FAD
Which of the following reactions involves a substrate level phosphorylation? - CORRECT
ANSWER - succinyl-CoA to succinate
The carbon skeletons of which of the following can be incorporated directly into the protein?
a. malate
b. succinate
c. a-ketoglutarate
d. oxaloacetate
e. both C and D are correct - CORRECT ANSWER - both C and D are correct
Which of the following is a positive effector of isocitrate dehydrogenase? - CORRECT
ANSWER - ADP
Which of the following is not directly required for the activity of pyruvate dehydrogenase? -
CORRECT ANSWER - ATP
The overall reaction catalyzed by pyruvate dehydrogenase is which of the following?
a. CH3COCHO + NAD+ + CoASH -> CH3CHOSCoA + NADH
b. CH3COCOO- + FAD + CoASH -> CH3COSCoA + FADH2
c. CH3COCOO- + NAD+ + CoASH -> CH3COSCoA + NADH
d. CH3CH(OH)COO- + NADH + CoASH -> CH3CH(OH)COSCoA + NAD+
e. None of the above are correct
...what kind of fresh hell is this - CORRECT ANSWER - c. CH3COCOO- + NAD+ +
CoASH -> CH3COSCoA + NADH