Questions and Answers

State whether the following statements are true or false. The carrier molecules of the electron transport system are located in the cytosol.

• True
• False

Which of the following statements about the electron transport chain is true? Group of answer choices A) It is driven by ATP hydrolysis. B) It includes a series of hydrolysis reactions associated with mitochondrial membranes. C) It consists of a series of redox reactions D) It occurs in the cytoplasm of both prokaryotic and eukaryotic cells.

Which of the following statements about the electron transport chain is true? 1 Water is the last electron acceptor. 2 The electron transport chain is the first step in cellular respiration. 3 NADH and FADH2 donate their electrons to the chain. 4 Electrons gain energy as they move down the chain.

Which one of the following statements about the redox reactions of the electron transport chain is correct? 1 NADH gains electrons in the initial reaction of the electron transport chain. 2 The electron transport chain takes electrons from water and gives them to oxygen. 3 The oxidation of NADH is directly coupled to the reduction of oxygen to water. 4 The redox reactions of the electron transport chain are directly coupled to the movement of protons across a membrane. 5 The redox reactions of the electron transport chain are directly coupled with the synthesis of ATP.

Which of the following statements about the chemiosmotic synthesis of ATP is correct? 1 The energy for production of ATP from ADP comes directly from a gradient of electrons across the inner mitochondrial membrane. 2 Oxygen participates directly in the reaction that makes ATP from ADP and P. 3 The chemiosmotic synthesis of ATP requires that the electron transport in the inner mitochondrial membrane be coupled to proton transport across the same membrane. 4 The chemiosmotic synthesis of ATP occurs only in eukaryotic cells, because it occurs in mitochondria. 5 Chemiosmotic ATP synthesis requires oxygen.

Which statement about the citric acid cycle is correct? 1. The citric acid cycle oxidizes glucose to carbon dioxide. 2 The citric acid cycle produces most of the ATP that is subsequently used by the electron transport chain. 3 The citric acid cycle depends on the availability of NAD+, which is a product of glycolysis. 4 The last reaction in the citric acid cycle produces a product that is a substrate for the first reaction of the citric acid cycle. 5 The oxidation of compounds by the citric acid cycle requires molecular oxygen.

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 I

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

D Coenzyme Q accepts electrons from complex I and complex II

Which of the following steps in cellular respiration is associated with release of maximum number of ATP molecules?

A Glycolysis

B Kreb’s cycle

C Oxidative phosphorylation

D Reduction of NADP

Which of the following is the correct sequence of events in cellular respiration?

a. glycolysis, citric acid cycle, electron transport chain

b. glycolysis, preparatory reaction, citric acid cycle, electron transport chain

c. glycolysis, electron transport chain, preparatory reaction

d. citric acid cycle, glycolysis, electron transport chain, preparatory reaction

e. citric acid cycle, electron transport, glycolysis, preparatory reaction

Place the following events of the electron transport chain in order.

Rank the items from the event that occurs first to the event that occurs last.

Oxidation of NADH

Reduction of oxygen and formation of water

Release of energy for

ATP synthesis

Electrons leave the electron transport chain

Electrons enter the electron transport chain