Oxidative Phosphorylation: Uncover the Energy-Producing Powerhouse of Cells

Question 1

Explain the effects of rotenone and cyanide on oxidative phosphorylation and their implications for mitochondrial function.

Accepted Answer

Rotenone blocks electron transfer at complex I, reducing NADH oxidation and ATP production.

Accepted Answer

Cyanide inhibits cytochrome c oxidase, preventing oxygen reduction and ATP synthesis.

Answer

Rotenone enhances electron transfer efficiency, resulting in increased ATP production.

Answer

Cyanide stimulates ATP synthesis by increasing the proton gradient.

Question 2

What is a direct product of oxidative phosphorylation?

Accepted Answer

ATP

Answer

NADH

Answer

ADP

Answer

H2O

Question 3

What is the main function of the electron transport chain in oxidative phosphorylation?

Accepted Answer

Generating a proton gradient

Answer

Producing ATP directly

Answer

Shutting electrons

Answer

Oxidizing NADH and FADH2

Question 4

What is the significance of oxidative phosphorylation in cellular metabolism?

Accepted Answer

Producing most of the energy for cellular processes

Answer

Regulating metabolic pathways

Answer

Providing reducing equivalents

Answer

Synthesizing essential biomolecules

Question 5

What is the function of ubiquinone in oxidative phosphorylation?

Accepted Answer

Facilitating electron transfer between Complex I and III

Answer

Transporting protons between Complex I and IV

Answer

Synthesizing ATP directly

Answer

Regulating the electron transport chain

Question 6

During oxidative phosphorylation, which molecule serves as the final electron acceptor in the electron transport chain?

Accepted Answer

Oxygen

Answer

NADH

Answer

Cytochrome c

Answer

FADH2

Question 7

Oxidative phosphorylation is primarily responsible for which cellular process?

Accepted Answer

Generating ATP

Answer

Synthesizing proteins

Answer

Storing genetic material

Answer

Transporting molecules across membranes

Question 8

The inner mitochondrial membrane's impermeability to protons creates which type of gradient?

Accepted Answer

Proton gradient

Answer

pH gradient

Answer

Electrical gradient

Answer

Concentration gradient

Question 9

Oxidative phosphorylation is a process associated with:

Accepted Answer

Aerobic respiration

Answer

Anaerobic respiration

Answer

Fermentation

Answer

Glycolysis

Question 10

Which electron carriers donate electrons to the electron transport chain, specifically to Complex I and Complex II?

Accepted Answer

NADH and FADH2

Answer

Complex III and IV

Answer

Complex I and III

Answer

Complex II and IV

Question 11

Who is credited with proposing the chemiosmotic hypothesis for oxidative phosphorylation?

Accepted Answer

Peter Mitchell

Answer

Francis Crick

Answer

James Watson

Answer

Albert Einstein

Question 12

Which component of the electron transport chain pumps protons across the mitochondrial inner membrane, driving ATP synthesis?

Accepted Answer

Cytochrome c oxidase

Answer

NADH dehydrogenase

Answer

Cytochrome c reductase

Answer

ATP synthase

Question 13

What is the primary electron donor for oxidative phosphorylation in eukaryotic cells?

Accepted Answer

NADH

Answer

Glucose

Answer

Pyruvate

Answer

FADH2

Question 14

What is the primary function of the F0F1-ATPase enzyme in oxidative phosphorylation?

Accepted Answer

Synthesizing ATP using the proton gradient across the mitochondrial inner membrane

Answer

Pumping protons across the mitochondrial outer membrane

Answer

Transferring electrons from NADH to oxygen

Answer

Regulating the flow of protons through the electron transport chain

Question 15

Which statement about uncouplers in oxidative phosphorylation is accurate?

Accepted Answer

They decrease the proton gradient across the mitochondrial inner membrane.

Answer

They increase the efficiency of oxidative phosphorylation.

Answer

They stimulate the electron transport chain.

Answer

They have no effect on oxidative phosphorylation.

Question 16

What is the major product of oxidative phosphorylation?

Accepted Answer

ATP

Answer

NADH

Answer

FADH2

Answer

O2

Question 17

Which of the following is NOT a component of the mitochondrial electron transport chain?

Accepted Answer

ATP synthase

Answer

NADH dehydrogenase

Answer

Cytochrome c

Answer

Ubiquinone

Question 18

What is the final electron acceptor in the electron transport chain?

Accepted Answer

Oxygen

Answer

Cytochrome c

Answer

FADH2

Answer

NADH

Question 19

Which molecule is directly synthesized during oxidative phosphorylation?

Accepted Answer

ATP

Answer

NADH

Answer

ADP

Answer

FADH2

Question 20

What enzyme catalyzes the synthesis of ATP during oxidative phosphorylation?

Accepted Answer

ATP synthase

Answer

Succinate dehydrogenase

Answer

NADH dehydrogenase

Answer

Cytochrome c oxidase

Question 21

Which of the following is a factor that can inhibit oxidative phosphorylation?

Accepted Answer

Cyanide

Answer

ATP

Answer

Oxygen

Question 22

Which of the following is the chemiosmotic mechanism by which ATP synthase generates ATP?

Accepted Answer

Proton gradient

Answer

Electron gradient

Answer

Concentration gradient

Answer

Chemical gradient

Question 23

What is the function of ubiquinone in the electron transport chain?

Accepted Answer

Mobile electron carrier

Answer

Enzyme

Answer

Proton pump

Question 24

What is the main significance of oxidative phosphorylation in cellular metabolism?

Accepted Answer

Production of energy in the form of ATP

Answer

Breakdown of waste products

Answer

Synthesis of new proteins

Answer

Storage of excess nutrients