Biology 1002B Chapter Notes - Chapter 6: Nadh Dehydrogenase, Oxidative Phosphorylation, Succinate Dehydrogenase

23 views7 pages

lemonwater-buffalo91

4 Apr 2016

School

Department

Course

Professor

For unlimited access to Textbook Notes, a Class+ subscription is required.

Document Summary

All carbon atoms previously released as carbon dioxide. 6. 5a the electron transport chain converts the potential energy in nadh and fadh2 into a proton-motive force: Transfer of electrons from nadh2 and fadh2 to oxygen. 4 (super)complexes: complex i: nadh dehydrogenase, complex ii: succinate dehydrogenase, single peripheral membrane protein, complex iii: cytochrome complex, complex iv: cytochrome oxidase. Protons from matrix into intermembrane space as electrons pass through complexes i and. Iv: also during cyclic reduction/oxidation of uq. The proteins themselves do not transfer the electrons but rather is facilitated by nonprotein molecules: prosthetic groups: prosthetic groups for complexes i, iii, and iv. Prosthetic groups: redox-active cofactors that alternate between reduced and. Oxidized states as they accept electrons from upstream molecules and donate electrons downstream: e. g. Heme: where there is a central redox-active iron atom that alternates between. Fe2+ and fe3: complex i"s prosthetic group: flavin mononucleotide (fmn) reduced by electron from.

Related Questions

19. Which of the following is a component of Succinate dehydrogenase in Electron transport chain?

A. Niacin

B. FMN

C. FAD

D. Coenzyme Q

E. Lipoic acid

20. In electron transport the flow of electrons:

A. is bidirectional

B. goes from a high energy state to a low energy state

C. takes place in the outer mitochondrial membrane

D. are used to pump H+ into the mitochondrial matrix

21. Which of the following statements about the electron transport chain is NOT correct

A. It is located in the inner mitochondrion membrane

B. Cytochrome c accepts electrons from complex II

C. Cytochrome c oxidase (complex IV) accepts electrons from Cytochrome c

D. Complex I is called NADH dehydrogenase

E. Coenzyme Q accepts electrons from complex I and complex II

22. In the electron transport chain, the enzyme cytochrome C oxidase:

A. Uses H2O as a substrate

B. Produces HOOH as a product

C. Cannot function if oxygen is absent

D. Accepts electrons from hydrogen ions

E. Uses ADP and Pi as substrates

Can you answer the following questions:

1. Carbon monoxide is considered toxic because it acts on Complex IV. How would the addition of carbon monoxide to actively respiring mitochondria affect the relative oxidation-reduction states of all components of the electron-transport chain?

A) All four complexes would remain oxidized because they function as a multisystem complex.

B) Complexes I and III would be reduced, but complexes II and IV would be oxidized because the

electrons come from FADH2 oxidation, not NADH.

C) Complexes I, II, and III would be oxidized but Complex IV would remain reduced.

D) Complexes I, II, and III would be reduced and Complex IV would be oxidized.

E) All four complexes would remain reduced because they function as a multisystem complex.

2. Electrons are not very soluble in hydrophobic environments such as a bilipid membrane. What evidence is there that electrons move from complex to complex through the lipid membrane?

A) Cytochrome C is the electron carrier in the membrane and undergoes a head-over-heel flip to set up the proton gradient.

B) Cytochrome C is the electron carrier in the membrane and contains a cydrophoric porphyrin center.

C) CoQ is the electron carrier within the membrane and seems to be confined to the respirasome.

D) CoQ is the electron carrier within the membrane and it contains a hydrophobic porphyrin center.

E) FeS clusters are the carriers within the membrane and the electrons move from one cluster to the

next in a chain-like fashion.

3. What is the rationale for saying that âelectrons flow down the electron-transport chainâ?

A) Electrons flow from oxidized carriers to reduced carriers in discrete steps like a staircase.

B) Electrons flow from half-reactions with more positive redox potentials to more negative.

C) Electrons flow from reactions that continuously generate negative free energy values.

D) Electrons flow from the outer surface to the inner surface, a top down perception.

E) Because we think of electrons flowing like a liquid, the only direction electrons can flow is down.

Why does an electron have lower potential energy in an H-O bondthan in an O=O bond?

H has a higher electronegativity than O.

O=O is not stable.

O=O contains a double bond.

The electrons are closer to the oxygen atom in the H-O bond.

None of the answers are correct.

How is the energy from the electron transport chain used mostdirectly?

to form the bonds of a water molecule

to pump hydrogen ions across the mitochondrial inner membraneinto the mitochondrial intermembrane space

to join ADP with a phosphate

to decompose glucose into pyruvate

to rotate ATP synthase

Which process provides the energy needed to pump protons acrossthe mitochondrial membrane during oxidative phosphorylation?

the transfer of electrons in redox reactions

the breakdown of ATP to ADP

the rotation of the ATP synthase rotor

oxidation of isocitrate

None of the answers are correct.

What causes the ATP synthase rotor to spin?

the passing of electrons through ATP synthase

the movement of protons across the mitochondrial membrane

the movement of electrons across the mitochondrial membrane

the synthesis of ATP from ADP and a phosphate group

None of the answers are correct.

What of the following generates the proton-motive force duringoxidative phosphorylation?

buildup of NADH molecules at protein complex I

movement of H⁺ ions across the mitochondrial membraneduring electron transport

rotation of the ATP synthase rotor

joining of H⁺ ions with oxygen to form water

None of the answers are correct.

Suppose a microorganism invades a cell, causing damage to ATPsynthase. How would cellular respiration be affected?

Electrons could not be passed down the electron transportchain.

ADP could not be joined with a phosphate to form ATP.

Hydrogen ions could not be pumped into the mitochondrialintermembrane space.

The cell could not release any energy from the glucosemolecule.

Glucose could not be broken down into pyruvate.

Which molecules transport electrons from the citric acid cycleto the electron transport chain?

NADH and FADH₂

ATP and ADP

GTP and GDP

oxaloacetate and citric acid

None of the answers are correct.

Which type of reactions control the energy release from glucoseduring the citric acid cycle?

acid-base reactions

redox reactions

random reactions

All answers are correct.

None of the answers are correct.

What is the role of NAD⁺ in cellular respiration?

to receive electrons from the citric acid cycle and deliver themto the electron transport chain

to catalyze the synthesis of ATP from ADP

to accumulate in the mitochondrial intermembrane space tofacilitate ATP synthesis

to serve as a substrate to bind to acetyl-CoA at the beginningof the citric acid cycle

None of the answers are correct.

10.

Which molecule enters the citric acid cycle?

glucose

pyruvate

ATP

acetyl-CoA

None of the answers are correct.

apricotgoose897

Biology 1002B Chapter Notes - Chapter 6: Nadh Dehydrogenase, Oxidative Phosphorylation, Succinate Dehydrogenase

Document Summary

Get access

Related Documents

Biology 1002B Chapter Notes - Chapter 4.4: Nadh Dehydrogenase, Cytochrome C Oxidase, Oxidative Phosphorylation

Biology 1002B Chapter Notes - Chapter 6.5 & 6.7a: Cellular Respiration, Cytosol, Pyruvic Acid

Biology 1002B Lecture Notes - Lecture 11: Cytochrome C Oxidase, Cytosol, Adipose Tissue

Related Questions