Question 1

Which of the following best describes the role of NAD+ in cellular respiration?

Accepted Answer

NAD+ acts as an electron carrier, accepting electrons during oxidation reactions.

Question 2

During glycolysis, which molecule is oxidized and which is reduced?

Accepted Answer

Glucose is oxidized and NAD+ is reduced.

Question 3

Which of the following equations correctly represents the reduction of NAD+?

Accepted Answer

$$\mathrm{NAD}^+ + \mathrm{H}^+ + 2e^- \rightarrow \mathrm{NADH}$$

Question 4

In the context of oxidative phosphorylation, what is the primary function of the proton gradient across the inner mitochondrial membrane?

Accepted Answer

To provide the energy required for ATP synthesis via ATP synthase.

Question 5

Which molecule is reduced as a result of the electron transport chain in mitochondria?

Accepted Answer

O$$_2$$

Question 6

What is the main purpose of chemiosmosis in cellular respiration?

Accepted Answer

To use the energy of a proton gradient to drive the synthesis of ATP.

Question 7

Which of the following best describes the energy transformation that occurs as protons flow through ATP synthase?

Accepted Answer

Potential energy is converted to kinetic energy.

Question 8

If the inner mitochondrial membrane becomes permeable to protons, what would be the most immediate effect on ATP synthesis?

Accepted Answer

ATP synthesis would decrease because the proton gradient would dissipate.

Question 9

Which of the following statements about the oxidation of NADH is correct?

Accepted Answer

It is an exergonic process that releases energy to pump protons across the membrane.

Question 10

Which of the following best explains why oxygen is essential for cellular respiration in eukaryotes?

Accepted Answer

Oxygen acts as the final electron acceptor in the electron transport chain, allowing the chain to continue functioning.

Question 11

Which of the following is a correct description of substrate-level phosphorylation?

Accepted Answer

ATP is produced directly by the transfer of a phosphate group from a substrate to ADP.

Question 12

During the process of oxidative phosphorylation, which of the following occurs?

Accepted Answer

Electrons are transferred from NADH and FADH2 to oxygen, forming water.

Question 13

Which of the following best describes the relationship between exergonic and endergonic reactions in cellular respiration?

Accepted Answer

Exergonic reactions release energy that is used to drive endergonic reactions such as ATP synthesis.

Question 14

Which of the following is the correct sequence of events in the electron transport chain?

Accepted Answer

Electrons are transferred from NADH to oxygen, protons are pumped across the membrane, ATP is synthesized.

Question 15

A patient is diagnosed with a genetic disorder that impairs the function of ATP synthase. Which of the following would most likely be observed in this patient’s cells?

Accepted Answer

A decreased rate of ATP production despite a normal proton gradient.

Question 16

Which of the following best explains why the inner mitochondrial membrane is compared to a dam in the provided analogy?

Accepted Answer

It holds back protons, creating potential energy, similar to how a dam holds back water.

Question 17

Which of the following is a direct result of the hydrolysis of ATP?

Accepted Answer

Release of energy that can be used to drive endergonic reactions.

Question 18

Which of the following best describes the fate of the electrons carried by NADH during cellular respiration?

Accepted Answer

They are transferred to oxygen, which is reduced to form water.

Question 19

Which of the following statements about redox reactions in cellular respiration is correct?

Accepted Answer

Oxidation is the loss of electrons, and reduction is the gain of electrons.

NAD, Cellular Respiration, and Oxidative Phosphorylation: Study Notes

Guida di studio - Domande di pratica

Study guide - Flashcard