Exam 3 Cellular Respiration Practice Questions

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

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

During the energy payoff phase of glycolysis, __________. a) glucose is phosphorylated before it is split into two three-carbon molecules b) NADH is produced c) ATP is produced d) glucose is phosphorylated after it is split into two three-carbon molecules e) NADH and ATP are produced

NADH and ATP are produced

Which of the following is a correct description of the events of cellular respiration and the sequence of events in cellular respiration? a) Oxidation of pyruvate; TCA cycle; oxidation of glucose to pyruvate; oxidative phosphorylation b) Glycolysis; oxidative phosphorylation; TCA cycle; oxidation of pyruvate c) Oxidation of glucose to pyruvate; reduction of pyruvate; TCA cycle; oxidative phosphorylation d) Oxidation of glucose to pyruvate; oxidation of pyruvate; oxidation of acetyl-coA; oxidative phosphorylation e) Glycolysis; reduction of pyruvate; TCA cycle; oxidative phosphorylation

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

In preparing pyruvate to enter the citric acid cycle, which of the following steps occurs? a) 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 ionized directly to acetyl-coA. c) Pyruvate is reduced and decarboxylated, and the resulting electrons oxidize an NAD+ to an NADH. d) Pyruvate is oxidized and decarboxylated, and the resulting electrons are donated to NADH to produce NAD+. e) Pyruvate is oxidized and decarboxylated, and the removed electrons are used to reduce an NAD+ to an NADH.

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

The energy from the electrons in NADH and FADH2 fuel what process in the electron transport chain? a) The movement of H+ through ATP synthase b) The pumping of H+ across the cristae of the mitochondrion c) chemiosmosis d) The electrons in NADH and FADH2 are not involved in the electron transport chain. e) The oxidation of oxygen

The pumping of H+ across the cristae of the mitochondrion

Glucose is the primary fuel for cellular respiration. Which of the following molecules can also be used by cellular respiration to generate ATP? a) fatty acids b) none of the listed c) amino acids d) glycerol e) all of them

all of them

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) feedback inhibition of glycolysis b) denaturing of the enzymes in glycolysis c) positive feedback d) slowing down ATP production from fermentation e) slowing down ATP production from oxidative phosphorylation

feedback inhibition of glycolysis

During the energy investment phase of glycolysis, __________. a) ATP is produced b) NADH is produced c) carbon dioxide is produced d) glucose is phosphorylated before it is split into 3-carbon molecules e) glucose is phosphorylated after it is split into 3-carbon molecules

glucose is phosphorylated before it is split into 3-carbon molecules

In the overall process of glycolysis and cellular respiration, __________ is oxidized and __________ is reduced.

glucose; oxygen

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) it is oxidized with carbon to form CO2 d) oxygen has no role in the electron transport chain e) it is oxidized to form ADP

it is reduced to form water

Most of the electrons removed from glucose by cellular respiration are used for which of the following processes? a) Reducing NAD+ to NADH in glycolysis and the citric acid cycle b) producing a proton gradient for ATP synthesis in the mitochondria c) producing a proton gradient for ATP synthesis in the mitochondria AND driving substrate-level phosphorylation in glycolysis d) driving substrate-level phosphorylation in glycolysis e) reducing NAD+ to NADH in glycolysis and the citric acid cycle AND producing a proton gradient for ATP synthesis in the mitochondria

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

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) glycolysis d) the electron transport chain and oxidative phosphorylation e) substrate-level phosphorylation

the electron transport chain and oxidative phosphorylation