Chapter 9 Module

In which process is glucose oxidized to form two molecules of pyruvate? A) Glycolysis B) Fermentation C) Chemiosmosis D) Electron transport chain E) Citric acid cycle

A) Glycolysis

What is the role of oxygen in the electron transport chain? A) It is reduced to form water. B) It is reduced to form CO2. C) Oxygen has no role in the electron transport chain. D) It is oxidized to form ADP. E) It is oxidized with carbon to form CO2.

A) It is reduced to form water.

What is the total production of ATP, NADH, and FADH2 in the citric acid cycle from one molecule of glucose? A) Two ATP, six NADH, and two FADH2 B) The citric acid cycle does not produce any of these molecules. C) 32 ATP only D) One ATP, three NADH, and one FADH2 E) Four ATP only

A) Two ATP, six NADH, and two FADH2

Which of the following pairs of pathways and their location in the cell is incorrectly matched? A) All of the responses are correctly matched. B) Citric acid cycle: cytosol C) Oxidative phosphorylation: mitochondrion D) Glycolysis: cytosol E) Electron transport chain: mitochondrion

B) Citric acid cycle: cytosol

Which metabolic pathway is common to both fermentation and cellular respiration of a glucose molecule? A) The citric acid cycle B) Glycolysis C) The electron transport chain D) Synthesis of acetyl CoA from pyruvate E) Reduction of pyruvate to lactate

B) Glycolysis

After completion of the citric acid cycle, most of the usable energy from the original glucose molecule is in the form of __________. A) acetyl CoA B) NADH C) CO2 D) ATP E) FADH2

B) NADH

In what molecule(s) is the majority of the chemical energy from pyruvate transferred during the citric acid cycle? A) Glucose B) NADH and FADH2 C) ADP D) Oxygen and carbon dioxide E) ATP

B) NADH and FADH2

In preparing pyruvate to enter the citric acid cycle, which of the following steps occurs? A) Pyruvate is oxidized and decarboxylated, and the resulting electrons are donated to NADH to produce NAD+. B) Pyruvate is oxidized and decarboxylated, and the removed electrons are used to reduce an NAD+ to an NADH. C) Pyruvate is ionized directly to acetyl-coA. D) Pyruvate is reduced and decarboxylated, and the resulting electrons oxidize an NAD+ to an NADH. E) Pyruvate is reduced to acetyl-coA, which involves the reduction of pyruvate, the addition of a carbon dioxide from the environment, and its reduction by NADH.

B) Pyruvate is oxidized and decarboxylated, and the removed electrons are used to reduce an NAD+ to an NADH.

Most of the NADH that delivers electrons to the electron transport chain comes from which of the following processes? A) Anabolic pathways B) The citric acid cycle C) Glycolysis D) Oxidative phosphorylation E) Substrate-level phosphorylation

B) The citric acid cycle

Which part of the catabolism of glucose by cellular respiration requires molecular oxygen (O2) and produces CO2? A) Glycolysis B) The combination of the citric acid cycle and electron transport C) The combination of glycolysis and the citric acid cycle D) The electron transport chain E) The citric acid cycle

B) The combination of the citric acid cycle and electron transport

A small amount of ATP is made in glycolysis by which of the following processes? A) Harnessing energy from the sun B) Transfer of a phosphate group from a fragment of glucose to ADP by substrate-level phosphorylation C) Transport of electrons through a series of carriers D) Attachment of a free inorganic phosphate (Pi) group to ADP to make ATP E) Transfer of electrons and hydrogen atoms to NAD+

B) Transfer of a phosphate group from a fragment of glucose to ADP by substrate-level phosphorylation

In the overall process of glycolysis and cellular respiration, __________ is oxidized and __________ is reduced. A) carbon dioxide; water B) glucose; oxygen C) ATP; oxygen D) oxygen; ATP E) glucose; ATP

B) glucose; oxygen

During aerobic respiration, molecular oxygen (O2) is used for which of the following purposes? A) Between glycolysis and the citric acid cycle to split a carbon from pyruvate, producing CO2 B) At the end of glycolysis to oxidize pyruvate C) At the end of the electron transport chain to accept electrons and form H2O D) As a source of O2 in every reaction that produces CO2 E) At the end of the citric acid cycle to regenerate citric acid

C) At the end of the electron transport chain to accept electrons and form H2O

Fermentation by itself produces no ATP but keeps glycolysis going, which produces a small amount of ATP. How does fermentation do this? A) Fermentation produces NADH, which fuels the electron transport chain and facilitates chemiosmosis. B) Fermentation oxidizes the carbons in pyruvate to CO2, which is then used in glycolysis. C) Fermentation oxidizes NADH to NAD+, which facilitates the production of ATP in glycolysis. D) Fermentation reduces NAD+ to NADH, which facilitates the production of ATP in glycolysis. E) Fermentation produces lactate, which keeps glycolysis going.

C) Fermentation oxidizes NADH to NAD+, which facilitates the production of ATP in glycolysis.

Which of the following is a correct description of the events of cellular respiration and the sequence of events in cellular respiration? A) Glycolysis; reduction of pyruvate; TCA cycle; oxidative phosphorylation B) Glycolysis; oxidative phosphorylation; TCA cycle; oxidation of pyruvate C) Oxidation of glucose to pyruvate; oxidation of pyruvate; oxidation of acetyl-coA; oxidative phosphorylation D) Oxidation of pyruvate; TCA cycle; oxidation of glucose to pyruvate; oxidative phosphorylation E) Oxidation of glucose to pyruvate; reduction of pyruvate; TCA cycle; oxidative phosphorylation

C) Oxidation of glucose to pyruvate; oxidation of pyruvate; oxidation of acetyl-coA; oxidative phosphorylation

Which of the following metabolic pathways produce(s) the most ATP, per glucose molecule metabolized, during cellular respiration? A) Fermentation B) Citric acid cycle C) The electron transport chain and oxidative phosphorylation D) Substrate-level phosphorylation E) Glycolysis

C) The electron transport chain and oxidative phosphorylation

The ATP synthase in a human cell obtains energy for synthesizing ATP directly from which of the following processes? A) The movement of electrons through a series of carriers B) The oxidation of NADH and FADH2 C) The flow of H+ across the inner mitochondrial membrane through the ATP synthase enzyme D) The reduction of oxygen E) The oxidation of glucose

C) The flow of H+ across the inner mitochondrial membrane through the ATP synthase enzyme

During the energy investment phase of glycolysis, __________. A) NADH is produced B) ATP is produced C) glucose is phosphorylated before it is split into two three-carbon molecules D) glucose is phosphorylated after it is split into two three-carbon molecules E) carbon dioxide is produced

C) glucose is phosphorylated before it is split into two three-carbon molecules

Muscle tissues make lactate from pyruvate to do which of the following? A) produce additional CO2 B) utilize the energy in pyruvate C) regenerate NAD+ D) speed up the rate of glycolysis E) get rid of pyruvate produced by glycolysis

C) regenerate NAD+

Glucose is the primary fuel for cellular respiration. Which of the following molecules can also be used by cellular respiration to generate ATP? A) Glycerol B) None of the listed responses is correct. C) Fatty acids D) All of the listed responses are correct. E) Amino acids

D) All of the listed responses are correct.

Most of the ATP in cellular respiration is produced by the process of chemiosmosis. How does this process produce ATP? A) Phosphates are stripped from phosphorylated sugars during the energy payoff phase. B) Through substrate-level phosphorylation C) Electrons from NADH and FADH2 are used to add a phosphate to ADP. D) H+ flows across the inner mitochondrial membrane through the enzyme ATP synthase. E) Pyruvate is oxidized, providing energy to add a phosphate to ADP.

D) H+ flows across the inner mitochondrial membrane through the enzyme ATP synthase.

molecule becomes more oxidized when it __________. A) (H+) ion B) loses a hydrogen C) gains a hydrogen D) loses an electron E) gains an electron F) changes shape

D) loses an electron

Cells must regulate their metabolic pathways so that they do not waste resources. What is the most common mechanism that regulates cellular respiration in most cells? A) Slowing down ATP production from oxidative phosphorylation B) Positive feedback C) Slowing down ATP production from fermentation D) Denaturing of the enzymes in glycolysis E) Feedback inhibition of glycolysis

E) Feedback inhibition of glycolysis

Which statement correctly describes the difference between alcohol fermentation and lactic acid fermentation? A) Alcohol fermentation produces lactate, and lactic acid fermentation produces ethanol. B) None of the listed responses is correct. C) Alcohol fermentation is an aerobic pathway, and lactic acid fermentation is an anaerobic pathway. D) Only lactic acid fermentation produces NAD+ to facilitate the production of ATP in glycolysis. E) Lactic acid fermentation produces lactate, and alcohol fermentation produces ethanol.

E) Lactic acid fermentation produces lactate, and alcohol fermentation produces ethanol.

During the energy payoff phase of glycolysis, __________. A) ATP is produced B) glucose is phosphorylated before it is split into two three-carbon molecules C) NADH is produced D) glucose is phosphorylated after it is split into two three-carbon molecules E) NADH and ATP are produced

E) NADH and ATP are produced

All of the processes involved in cellular respiration produce ATP. Which of the following processes produces the most ATP? A) Citric acid cycle B) Glycolysis C) Substrate-level phosphorylation D) Fermentation E) Oxidative phosphorylation

E) Oxidative phosphorylation

Most of the electrons removed from glucose by cellular respiration are used for which of the following processes? A) Producing a proton gradient for ATP synthesis in the mitochondria B) Producing a proton gradient for ATP synthesis in the mitochondria AND driving substrate-level phosphorylation in glycolysis C) Driving substrate-level phosphorylation in glycolysis D) Reducing NAD+ to NADH in glycolysis and the citric acid cycle E) Reducing NAD+ to NADH in glycolysis and the citric acid cycle AND producing a proton gradient for ATP synthesis in the mitochondria.

E) Reducing NAD+ to NADH in glycolysis and the citric acid cycle AND producing a proton gradient for ATP synthesis in the mitochondria.

Fermentation is essentially glycolysis plus an extra step in which pyruvate is reduced to form lactate or alcohol and carbon dioxide. This last step __________. A) removes poisonous oxygen from the environment B) prevents pyruvate from accumulating C) enables the cell to make pyruvate into substances it can use D) extracts a bit more energy from glucose E) enables the cell to recycle the reduced NADH to oxidized NAD+

E) enables the cell to recycle the reduced NADH to oxidized NAD+