UNE Biochemistry Midterm Study Bank
UPDATED Questions with CORRECT
Answers
Succinate is a substrate for which complex in the electron transport chain?
a.) Complex 1 (NADH-1 oxidoreductase)
b.) Complex IV (Cyt c oxidase)
c.) Complex V (ATP synthase)
d.) complex II (Succinate-Q reductase) - CORRECT ANSWER - Complex II (succinate-Q
reductase) (D)
Which of the following would be consistent with an exergonic reaction?
a.) ∆S would be negative
b.) ∆G would be negative
c.) ∆S would be positive
d.)∆G would be positive - CORRECT ANSWER - ∆G would be negative (B)
Which of the following describes the malate-aspartate shuttle system?
a.) Carries NADH from the cytoplasm directly into the mitochondria
,b.) Generates 2.5 molecules of ATP in mitochondria per each NADH from glycolysis
c.) Moves NADH from the mitochondria to the cytoplasm
d.) Relies on malate dehydrogenase in the inner mitochondrial membrane
e.) Requires reduction of pyruvate to lactate for oxidizing NADH - CORRECT
ANSWER - Generates 2.5 molecules of ATP in mitochondria per each NADH from
glycolysis (B)
ATP is a high energy molecule that is often hydrolyzed during reactions. The energy within ATP
is stored primarily in which of the following components of the molecule?
a.) In the high energy phosphate bonds
b.) In the adenine base
c.) In the D-ribose group - CORRECT ANSWER - In the high energy phosphate bonds (A)
Dinitrophenol is an uncoupler of the electron transport chain. The addition of dinitrophenol will
have which of the following impacts?
a.) Decrease the pH of the intermembrane space
b.) Increase oxygen consumption
c.) Decrease oxidation of NADH
,d.) Increase ATP production - CORRECT ANSWER - Increase oxygen consumption (B)
In the malate aspartate shuttle, glutamate is converted to _______ in the mitochondria while
aspartate is converted to _______ in the cytosol.
a.) Oxaloacetate; malate
b.) alpha-ketoglutarate; oxaloacetate
c.) Oxaloacetate; glutamate
d.) Aspartate; alpha-ketoglutarate
e.) Malate; oxaloacetate - CORRECT ANSWER - alpha-ketoglutarate; oxaloacetate (B)
The glycerophosphate shuttle is a major shuttle of most tissues. Which of the following best
describes the transfer of electrons by this shuttle?
a.) Electrons are directly transferred from glycerol-3-phosphate to NAD containing glycerol
phosphate dehydrogenase
b.) Electrons are directly transferred from glycerol-3-phosphate to an FAD containing glycerol
phosphate dehydrogenase
c.) Electrons are directly transferred from DHAP (dihydroxyacetone phosphate) to an FAD
containing glycerol phosphate dehydrogenase
d.) Electrons are directly transferred from glycerol-3-phosphate and DHAP - CORRECT
ANSWER - Electrons are directly transferred from glycerol-3-phosphate to FAD
containing glycerol phosphate dehydrogenase (B)
, Heat can be generated by brown adipose tissue in hibernating mammals. Which of the following
is most likely the mechanism by which this occurs?
a.) Increased ATP production by ATP synthase
b.) Expression of a protein that uncouples the ETC
c.) An increased pH gradient across the inner mitochondrial membrane
d.) A decrease in oxygen consumption - CORRECT ANSWER - Expression of a protein
that uncouples the ETC (B)
Allosteric activators of hemoglobin will increase binding through what mechanism? -
CORRECT ANSWER - Binding the protein, and keeping it in the "R" conformation
An enzyme has a mutation within the substate binding site that reduces the binding of the
coenzyme needed for covalent catalysis. What is likely to result as a consequence of this
mutation? - CORRECT ANSWER - The enzyme will not be able to form the transition
state complex
How do most enzymes reduce activation energy needed to move a reaction forward? -
CORRECT ANSWER - Providing an active site most complimentary to the transition state
Under which energy conditions, AMP will bind to phosphofructokinase 1 (PFK1) and glycogen
phosphorylase at site unique of the active site. This enhances the activity of these enzymes. This
is an example of which of the following types of enzyme regulation?
a.) Allosteric activation
b.) Allosteric inhibition
UPDATED Questions with CORRECT
Answers
Succinate is a substrate for which complex in the electron transport chain?
a.) Complex 1 (NADH-1 oxidoreductase)
b.) Complex IV (Cyt c oxidase)
c.) Complex V (ATP synthase)
d.) complex II (Succinate-Q reductase) - CORRECT ANSWER - Complex II (succinate-Q
reductase) (D)
Which of the following would be consistent with an exergonic reaction?
a.) ∆S would be negative
b.) ∆G would be negative
c.) ∆S would be positive
d.)∆G would be positive - CORRECT ANSWER - ∆G would be negative (B)
Which of the following describes the malate-aspartate shuttle system?
a.) Carries NADH from the cytoplasm directly into the mitochondria
,b.) Generates 2.5 molecules of ATP in mitochondria per each NADH from glycolysis
c.) Moves NADH from the mitochondria to the cytoplasm
d.) Relies on malate dehydrogenase in the inner mitochondrial membrane
e.) Requires reduction of pyruvate to lactate for oxidizing NADH - CORRECT
ANSWER - Generates 2.5 molecules of ATP in mitochondria per each NADH from
glycolysis (B)
ATP is a high energy molecule that is often hydrolyzed during reactions. The energy within ATP
is stored primarily in which of the following components of the molecule?
a.) In the high energy phosphate bonds
b.) In the adenine base
c.) In the D-ribose group - CORRECT ANSWER - In the high energy phosphate bonds (A)
Dinitrophenol is an uncoupler of the electron transport chain. The addition of dinitrophenol will
have which of the following impacts?
a.) Decrease the pH of the intermembrane space
b.) Increase oxygen consumption
c.) Decrease oxidation of NADH
,d.) Increase ATP production - CORRECT ANSWER - Increase oxygen consumption (B)
In the malate aspartate shuttle, glutamate is converted to _______ in the mitochondria while
aspartate is converted to _______ in the cytosol.
a.) Oxaloacetate; malate
b.) alpha-ketoglutarate; oxaloacetate
c.) Oxaloacetate; glutamate
d.) Aspartate; alpha-ketoglutarate
e.) Malate; oxaloacetate - CORRECT ANSWER - alpha-ketoglutarate; oxaloacetate (B)
The glycerophosphate shuttle is a major shuttle of most tissues. Which of the following best
describes the transfer of electrons by this shuttle?
a.) Electrons are directly transferred from glycerol-3-phosphate to NAD containing glycerol
phosphate dehydrogenase
b.) Electrons are directly transferred from glycerol-3-phosphate to an FAD containing glycerol
phosphate dehydrogenase
c.) Electrons are directly transferred from DHAP (dihydroxyacetone phosphate) to an FAD
containing glycerol phosphate dehydrogenase
d.) Electrons are directly transferred from glycerol-3-phosphate and DHAP - CORRECT
ANSWER - Electrons are directly transferred from glycerol-3-phosphate to FAD
containing glycerol phosphate dehydrogenase (B)
, Heat can be generated by brown adipose tissue in hibernating mammals. Which of the following
is most likely the mechanism by which this occurs?
a.) Increased ATP production by ATP synthase
b.) Expression of a protein that uncouples the ETC
c.) An increased pH gradient across the inner mitochondrial membrane
d.) A decrease in oxygen consumption - CORRECT ANSWER - Expression of a protein
that uncouples the ETC (B)
Allosteric activators of hemoglobin will increase binding through what mechanism? -
CORRECT ANSWER - Binding the protein, and keeping it in the "R" conformation
An enzyme has a mutation within the substate binding site that reduces the binding of the
coenzyme needed for covalent catalysis. What is likely to result as a consequence of this
mutation? - CORRECT ANSWER - The enzyme will not be able to form the transition
state complex
How do most enzymes reduce activation energy needed to move a reaction forward? -
CORRECT ANSWER - Providing an active site most complimentary to the transition state
Under which energy conditions, AMP will bind to phosphofructokinase 1 (PFK1) and glycogen
phosphorylase at site unique of the active site. This enhances the activity of these enzymes. This
is an example of which of the following types of enzyme regulation?
a.) Allosteric activation
b.) Allosteric inhibition
