Module 7, Mod7,8, Medical Biochemistry
Unit 1 Exam, Week 2 Evaluation, Pre-
Evaluation Question Bank, 1
In the malate aspartate shuttle, glutamate is converted to
_________ in the mitochondria while aspartate is converted to
___________ in the cytosol correct answer: α-ketoglutarate;
oxaloacetate
Which of the following describes a correct and complete
electron transfer pathway necessary for oxidative
phosphorylation?
From NADH to ATP synthase correct answer: NADH →
complex I → CoQ → complex III → cyt c → complex IV
The synthesis of large molecules from smaller compounds is an
example of what type of work? correct answer: Biochemical
Work
The fully reduced quinol form of CoQ contains which of the
following combinations of electrons and protons? correct
answer: Two electrons and Two Protons
Complex II (succinate dehydrogenase) is not considered to be
part of the process of oxidative phosphorylation becuase it is
unable to do what? correct answer: Pump Protons from the
mitochondrial matrix to the inter membrane space
,The reduction of NAD+ is often coupled to the oxidation of an
alcohol. In this reaction, NAD+ obtains which of the following
from the oxidized compound? correct answer: Two electrons as
a hydride ion
Heat ban be generated in the brown adipose tissue of hibernating
mammals due to which of the following processes? correct
answer: Uncoupling of the Electron Transport Chain by
thermogenin
The malate aspartame shuttle is used to move reducing
equivalents from cytosolic NADH into the mitochondria where
it can be oxyidized. Which of the following compounds is used
to move the reducing equivalents from cytosolic NADH into the
mitochondria. correct answer: Malate
As electrons flow through complexes in the inner mitochondrial
membrane, protons are pumped from the matrix to the
intermembrane space. Which of the following statements is most
reflective of the pH in the intermembrane space? correct answer:
The pH is higher in the matrix when compared to the
intermembrane space
glycerol 3-phosphate shuttle is the major shuttle of most tissues.
Which of the following best describes the transfer of electrons
by this shuttle? correct answer: Electrons are directly
transferred from glycerol 3-phosphate to an FAD containing
glycerol phosphate dehydrogenase
,The last cytochrome in the ETC, cytochrome oxidase, passes
electrons to O2. Cytochrome oxidase is able to do this because it
has:
Higher Km for oxygen than hgb
lower Km for oxygen than hgb
An iron-sulfer center
a bound iron molecule that can collect 4 electrons correct
answer: lower Km for oxygen than hemoglobin,
The lower Km for oxygen allows cytochrome oxidase to 'pull'
oxygen from myoglobin and hemoglobin, additionally it is
bound to copper ions that allows for the collection of 4 electrons
required for the reduction of oxygen.
Succinct is a substrate for which complex in the electron
transport chain?
Complex I
Complex IV
Complex II
Complex V correct answer: Complex II
Complex II or Succinate dehydrogenase is coupled to the TCA
cycle and accepts succinate rather than malate as a substrate
Which of the following is an example of mechanical work?
The energy required to oxidize NADH
The energy needed to Phosphorylase glucose
The energy needed to move sodium across the cell membrane
, The energy required to change the conformation of hgb correct
answer: The energy required to change the conformation of hgb
Mechanical work is best described as the conversion of a high
energy bond, such as that in an ATP bond, to instigate a
conformational change in a protein
In the case of an exothermic reaction:
ΔG0 Would be negative
ΔG0 Would be positive
ΔS would be positive
ΔS would be negative correct answer: ΔG0 would be negative
A negative ΔG0 is indicative of a spontaneous reaction. ΔS is
the change in entropy or an increase in disorder, this value is
often negligible
The addition of dinitrophenol (DNT) to the electron transport
chain will lead to an increase in O2 consumption. This is an
example of a(n):
Inhibitor
Oxidizing agent
Reducing agent
Uncoupler correct answer: Uncoupler
DNP is an uncouple of the electron transport train, dissipating
the proton gradient across the inner mitochondrial membrane
The formation of a double bond is most often coupled to which
of the following reactions?
Unit 1 Exam, Week 2 Evaluation, Pre-
Evaluation Question Bank, 1
In the malate aspartate shuttle, glutamate is converted to
_________ in the mitochondria while aspartate is converted to
___________ in the cytosol correct answer: α-ketoglutarate;
oxaloacetate
Which of the following describes a correct and complete
electron transfer pathway necessary for oxidative
phosphorylation?
From NADH to ATP synthase correct answer: NADH →
complex I → CoQ → complex III → cyt c → complex IV
The synthesis of large molecules from smaller compounds is an
example of what type of work? correct answer: Biochemical
Work
The fully reduced quinol form of CoQ contains which of the
following combinations of electrons and protons? correct
answer: Two electrons and Two Protons
Complex II (succinate dehydrogenase) is not considered to be
part of the process of oxidative phosphorylation becuase it is
unable to do what? correct answer: Pump Protons from the
mitochondrial matrix to the inter membrane space
,The reduction of NAD+ is often coupled to the oxidation of an
alcohol. In this reaction, NAD+ obtains which of the following
from the oxidized compound? correct answer: Two electrons as
a hydride ion
Heat ban be generated in the brown adipose tissue of hibernating
mammals due to which of the following processes? correct
answer: Uncoupling of the Electron Transport Chain by
thermogenin
The malate aspartame shuttle is used to move reducing
equivalents from cytosolic NADH into the mitochondria where
it can be oxyidized. Which of the following compounds is used
to move the reducing equivalents from cytosolic NADH into the
mitochondria. correct answer: Malate
As electrons flow through complexes in the inner mitochondrial
membrane, protons are pumped from the matrix to the
intermembrane space. Which of the following statements is most
reflective of the pH in the intermembrane space? correct answer:
The pH is higher in the matrix when compared to the
intermembrane space
glycerol 3-phosphate shuttle is the major shuttle of most tissues.
Which of the following best describes the transfer of electrons
by this shuttle? correct answer: Electrons are directly
transferred from glycerol 3-phosphate to an FAD containing
glycerol phosphate dehydrogenase
,The last cytochrome in the ETC, cytochrome oxidase, passes
electrons to O2. Cytochrome oxidase is able to do this because it
has:
Higher Km for oxygen than hgb
lower Km for oxygen than hgb
An iron-sulfer center
a bound iron molecule that can collect 4 electrons correct
answer: lower Km for oxygen than hemoglobin,
The lower Km for oxygen allows cytochrome oxidase to 'pull'
oxygen from myoglobin and hemoglobin, additionally it is
bound to copper ions that allows for the collection of 4 electrons
required for the reduction of oxygen.
Succinct is a substrate for which complex in the electron
transport chain?
Complex I
Complex IV
Complex II
Complex V correct answer: Complex II
Complex II or Succinate dehydrogenase is coupled to the TCA
cycle and accepts succinate rather than malate as a substrate
Which of the following is an example of mechanical work?
The energy required to oxidize NADH
The energy needed to Phosphorylase glucose
The energy needed to move sodium across the cell membrane
, The energy required to change the conformation of hgb correct
answer: The energy required to change the conformation of hgb
Mechanical work is best described as the conversion of a high
energy bond, such as that in an ATP bond, to instigate a
conformational change in a protein
In the case of an exothermic reaction:
ΔG0 Would be negative
ΔG0 Would be positive
ΔS would be positive
ΔS would be negative correct answer: ΔG0 would be negative
A negative ΔG0 is indicative of a spontaneous reaction. ΔS is
the change in entropy or an increase in disorder, this value is
often negligible
The addition of dinitrophenol (DNT) to the electron transport
chain will lead to an increase in O2 consumption. This is an
example of a(n):
Inhibitor
Oxidizing agent
Reducing agent
Uncoupler correct answer: Uncoupler
DNP is an uncouple of the electron transport train, dissipating
the proton gradient across the inner mitochondrial membrane
The formation of a double bond is most often coupled to which
of the following reactions?
