Question 1

Substrate-level phosphorylation accounts for approximately what percentage of the ATP formed by the reactions of glycolysis?

Accepted Answer

A)  0% 
B)  2% 
C)  10% 
D)  38% 
E)  100% 
A)  0% 
B)  2% 
C)  10% 
D)  38% 
E)  100%

Question 2

The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction

Accepted Answer

A)  gains electrons and gains potential energy. 
B)  loses electrons and loses potential energy. 
C)  gains electrons and loses potential energy. 
D)  loses electrons and gains potential energy. 
E)  neither gains nor loses electrons, but gains or loses potential energy. 
A)  gains electrons and gains potential energy. 
B)  loses electrons and loses potential energy. 
C)  gains electrons and loses potential energy. 
D)  loses electrons and gains potential energy. 
E)  neither gains nor loses electrons, but gains or loses potential energy.

Question 3

Which of the following normally occurs regardless of whether or not oxygen (O2) is present?

Accepted Answer

A)  glycolysis 
B)  fermentation 
C)  oxidation of pyruvate to acetyl CoA 
D)  citric acid cycle 
E)  oxidative phosphorylation (chemiosmosis) 
A)  glycolysis 
B)  fermentation 
C)  oxidation of pyruvate to acetyl CoA 
D)  citric acid cycle 
E)  oxidative phosphorylation (chemiosmosis)

Question 4

Where are the proteins of the electron transport chain located?

Accepted Answer

A)  cytosol 
B)  mitochondrial outer membrane 
C)  mitochondrial inner membrane 
D)  mitochondrial intermembrane space 
E)  mitochondrial matrix 
A)  cytosol 
B)  mitochondrial outer membrane 
C)  mitochondrial inner membrane 
D)  mitochondrial intermembrane space 
E)  mitochondrial matrix

Question 5

For each mole of glucose (C6H12O6) oxidized by cellular respiration, how many moles of CO2 are released in the citric acid cycle (see Figure 7.1)?

Accepted Answer

A)  2 
B)  4 
C)  6 
D)  12 
E)  3 
A)  2 
B)  4 
C)  6 
D)  12 
E)  3

Question 6

What is the term for metabolic pathways that release stored energy by breaking down complex molecules?

Accepted Answer

A)  anabolic pathways 
B)  catabolic pathways 
C)  fermentation pathways 
D)  thermodynamic pathways 
E)  bioenergetic pathways 
A)  anabolic pathways 
B)  catabolic pathways 
C)  fermentation pathways 
D)  thermodynamic pathways 
E)  bioenergetic pathways

Question 7

Brown fat cells produce a protein called thermogenin in their mitochondrial inner membrane. Thermogenin is a channel for facilitated transport of protons across the membrane. What will occur in the brown fat cells when they produce thermogenin?

Accepted Answer

A)  ATP synthesis and heat generation will both increase. 
B)  ATP synthesis will increase, and heat generation will decrease. 
C)  ATP synthesis will decrease, and heat generation will increase. 
D)  ATP synthesis and heat generation will both decrease. 
E)  ATP synthesis and heat generation will stay the same. 
A)  ATP synthesis and heat generation will both increase. 
B)  ATP synthesis will increase, and heat generation will decrease. 
C)  ATP synthesis will decrease, and heat generation will increase. 
D)  ATP synthesis and heat generation will both decrease. 
E)  ATP synthesis and heat generation will stay the same.

Question 8

A molecule that is phosphorylated

Accepted Answer

A)  has been reduced as a result of a redox reaction involving the loss of an inorganic phosphate. 
B)  has a decreased chemical reactivity; it is less likely to provide energy for cellular work. 
C)  has been oxidized as a result of a redox reaction involving the gain of an inorganic phosphate. 
D)  has an increased chemical potential energy; it is primed to do cellular work. 
E)  has less energy than before its phosphorylation and therefore less energy for cellular work. 
A)  has been reduced as a result of a redox reaction involving the loss of an inorganic phosphate. 
B)  has a decreased chemical reactivity; it is less likely to provide energy for cellular work. 
C)  has been oxidized as a result of a redox reaction involving the gain of an inorganic phosphate. 
D)  has an increased chemical potential energy; it is primed to do cellular work. 
E)  has less energy than before its phosphorylation and therefore less energy for cellular work.

Question 9

Even though plants carry on photosynthesis, plant cells still use their mitochondria for oxidation of pyruvate. When and where will this occur?

Accepted Answer

A)  in photosynthetic cells in the light, while photosynthesis occurs concurrently 
B)  in nonphotosynthesizing cells only 
C)  in cells that are storing glucose only 
D)  in all cells all the time 
E)  in photosynthesizing cells in the light and in other tissues in the dark 
A)  in photosynthetic cells in the light, while photosynthesis occurs concurrently 
B)  in nonphotosynthesizing cells only 
C)  in cells that are storing glucose only 
D)  in all cells all the time 
E)  in photosynthesizing cells in the light and in other tissues in the dark

Question 10

Which of the following statements describes the results of this reaction? C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy

Accepted Answer

A)  C6H12O6 is oxidized and O2 is reduced. 
B)  O2 is oxidized and H2O is reduced. 
C)  CO2 is reduced and O2 is oxidized. 
D)  C6H12O6 is reduced and CO2 is oxidized. 
E)  O2 is reduced and CO2 is oxidized. 
A)  C6H12O6 is oxidized and O2 is reduced. 
B)  O2 is oxidized and H2O is reduced. 
C)  CO2 is reduced and O2 is oxidized. 
D)  C6H12O6 is reduced and CO2 is oxidized. 
E)  O2 is reduced and CO2 is oxidized.

Question 11

Figure 7.1
The citric acid cycle.
-Starting with one molecule of isocitrate and ending with fumarate, how many ATP molecules can be made through substrate-level phosphorylation (see Figure 7.1)?

Accepted Answer

A)  1 
B)  2 
C)  11 
D)  12 
E)  24 
A)  1 
B)  2 
C)  11 
D)  12 
E)  24

Question 12

What happens at the end of the chain in Figure 7.2?

Accepted Answer

A)  Two electrons combine with a proton and a molecule of NAD+. 
B)  Two electrons combine with a molecule of oxygen and two hydrogen atoms. 
C)  Four electrons combine with a molecule of oxygen and 4 protons. 
D)  Four electrons combine with four hydrogen and two oxygen atoms. 
E)  One electron combines with a molecule of oxygen and a hydrogen atom. 
A)  Two electrons combine with a proton and a molecule of NAD+. 
B)  Two electrons combine with a molecule of oxygen and two hydrogen atoms. 
C)  Four electrons combine with a molecule of oxygen and 4 protons. 
D)  Four electrons combine with four hydrogen and two oxygen atoms. 
E)  One electron combines with a molecule of oxygen and a hydrogen atom.

Question 13

Why is glycolysis described as having an investment phase and a payoff phase?

Accepted Answer

A)  It both splits molecules and assembles molecules. 
B)  It attaches and detaches phosphate groups. 
C)  It uses glucose and generates pyruvate. 
D)  It shifts molecules from cytosol to mitochondrion. 
E)  It uses stored ATP and then forms a net increase in ATP. 
A)  It both splits molecules and assembles molecules. 
B)  It attaches and detaches phosphate groups. 
C)  It uses glucose and generates pyruvate. 
D)  It shifts molecules from cytosol to mitochondrion. 
E)  It uses stored ATP and then forms a net increase in ATP.

Question 14

When electrons move closer to a more electronegative atom, what happens?

Accepted Answer

A)  The more electronegative atom is reduced, and energy is released. 
B)  The more electronegative atom is reduced, and energy is consumed. 
C)  The more electronegative atom is oxidized, and energy is consumed. 
D)  The more electronegative atom is oxidized, and energy is released. 
E)  The more electronegative atom is reduced, and entropy decreases. 
A)  The more electronegative atom is reduced, and energy is released. 
B)  The more electronegative atom is reduced, and energy is consumed. 
C)  The more electronegative atom is oxidized, and energy is consumed. 
D)  The more electronegative atom is oxidized, and energy is released. 
E)  The more electronegative atom is reduced, and entropy decreases.

Question 15

In the absence of oxygen, yeast cells can obtain energy by fermentation, resulting in the production of

Accepted Answer

A)  ATP, CO2, and ethanol (ethyl alcohol). 
B)  ATP, CO2, and lactate. 
C)  ATP, NADH, and pyruvate. 
D)  ATP, pyruvate, and oxygen. 
E)  ATP, pyruvate, and acetyl CoA. 
A)  ATP, CO2, and ethanol (ethyl alcohol). 
B)  ATP, CO2, and lactate. 
C)  ATP, NADH, and pyruvate. 
D)  ATP, pyruvate, and oxygen. 
E)  ATP, pyruvate, and acetyl CoA.

Question 16

In a mitochondrion, if the matrix ATP concentration is high, and the intermembrane space proton concentration is too low to generate sufficient proton-motive force, then

Accepted Answer

A)  ATP synthase will increase the rate of ATP synthesis. 
B)  ATP synthase will stop working. 
C)  ATP synthase will hydrolyze ATP and pump protons into the intermembrane space. 
D)  ATP synthase will hydrolyze ATP and pump protons into the matrix. 
A)  ATP synthase will increase the rate of ATP synthesis. 
B)  ATP synthase will stop working. 
C)  ATP synthase will hydrolyze ATP and pump protons into the intermembrane space. 
D)  ATP synthase will hydrolyze ATP and pump protons into the matrix.

Question 17

One function of both alcohol fermentation and lactic acid fermentation is to

Accepted Answer

A)  reduce NAD+ to NADH. 
B)  reduce FAD+ to FADH2. 
C)  oxidize NADH to NAD+. 
D)  reduce FADH2 to FAD+. 
E)  do none of the above. 
A)  reduce NAD+ to NADH. 
B)  reduce FAD+ to FADH2. 
C)  oxidize NADH to NAD+. 
D)  reduce FADH2 to FAD+. 
E)  do none of the above.

Question 18

What is the oxidizing agent in the following reaction? Pyruvate + NADH + H+ → Lactate + NAD+

Accepted Answer

A)  oxygen 
B)  NADH 
C)  NAD+ 
D)  lactate 
E)  pyruvate 
A)  oxygen 
B)  NADH 
C)  NAD+ 
D)  lactate 
E)  pyruvate

Question 19

In vertebrate animals, brown fat tissue's color is due to abundant blood vessels and capillaries. White fat tissue, on the other hand, is specialized for fat storage and contains relatively few blood vessels or capillaries. Brown fat cells have a specialized protein that dissipates the proton-motive force across the mitochondrial membranes. Which of the following might be the function of the brown fat tissue?

Accepted Answer

A)  to increase the rate of oxidative phosphorylation from its few mitochondria 
B)  to allow the animals to regulate their metabolic rate when it is especially hot 
C)  to increase the production of ATP 
D)  to allow other membranes of the cell to perform mitochondrial functions 
E)  to regulate temperature by converting most of the energy from NADH oxidation to heat 
A)  to increase the rate of oxidative phosphorylation from its few mitochondria 
B)  to allow the animals to regulate their metabolic rate when it is especially hot 
C)  to increase the production of ATP 
D)  to allow other membranes of the cell to perform mitochondrial functions 
E)  to regulate temperature by converting most of the energy from NADH oxidation to heat

Question 20

When hydrogen ions are pumped from the mitochondrial matrix across the inner membrane and into the intermembrane space, the result is

Accepted Answer

A)  the formation of ATP. 
B)  the reduction of NAD+. 
C)  the restoration of the Na+/K+ balance across the membrane. 
D)  the creation of a proton-motive force. 
E)  the lowering of pH in the mitochondrial matrix. 
A)  the formation of ATP. 
B)  the reduction of NAD+. 
C)  the restoration of the Na+/K+ balance across the membrane. 
D)  the creation of a proton-motive force. 
E)  the lowering of pH in the mitochondrial matrix.

Exam 7: Cellular Respiration and Fermentation

Substrate-level phosphorylation accounts for approximately what percentage of the ATP formed by the reactions of glycolysis?

The molecule that functions as the reducing agent (electron donor) in a redox or oxidation-reduction reaction

Which of the following normally occurs regardless of whether or not oxygen (O2) is present?

Where are the proteins of the electron transport chain located?

For each mole of glucose (C6H12O6) oxidized by cellular respiration, how many moles of CO2 are released in the citric acid cycle (see Figure 7.1)?

What is the term for metabolic pathways that release stored energy by breaking down complex molecules?

Brown fat cells produce a protein called thermogenin in their mitochondrial inner membrane. Thermogenin is a channel for facilitated transport of protons across the membrane. What will occur in the brown fat cells when they produce thermogenin?

A molecule that is phosphorylated

Even though plants carry on photosynthesis, plant cells still use their mitochondria for oxidation of pyruvate. When and where will this occur?

Which of the following statements describes the results of this reaction? C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy

Figure 7.1 The citric acid cycle. -Starting with one molecule of isocitrate and ending with fumarate, how many ATP molecules can be made through substrate-level phosphorylation (see Figure 7.1)?

What happens at the end of the chain in Figure 7.2?

Why is glycolysis described as having an investment phase and a payoff phase?

When electrons move closer to a more electronegative atom, what happens?

In the absence of oxygen, yeast cells can obtain energy by fermentation, resulting in the production of

In a mitochondrion, if the matrix ATP concentration is high, and the intermembrane space proton concentration is too low to generate sufficient proton-motive force, then

One function of both alcohol fermentation and lactic acid fermentation is to

What is the oxidizing agent in the following reaction? Pyruvate + NADH + H+ → Lactate + NAD+

When hydrogen ions are pumped from the mitochondrial matrix across the inner membrane and into the intermembrane space, the result is

Introduction: Evolution and the Foundations of Biology

The Chemical Context of Life

Carbon and the Molecular Diversity of Life

A Tour of the Cell

Membrane Transport and Cell Signaling

An Introduction to Metabolism

Photosynthesis

The Cell Cycle

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

Regulation of Gene Expression

Development, Stem Cells, and Cancer

Viruses

Genomes and Their Evolution

Descent With Modification

Phylogeny

The Evolution of Populations

The Origin of Species

Broad Patterns of Evolution

Early Life and the Diversification of Prokaryotes

The Origin and Diversification of Eukaryotes

The Colonization of Land by Plants and Fungi

The Rise of Animal Diversity

Plant Structure and Growth

Resource Acquisition, Nutrition, and Transport in Vascular Plants

Reproduction and Domestication of Flowering Plants

Plant Responses to Internal and External Signals

Homeostasis and Endocrine Signaling

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Reproduction and Development

Neurons, Synapses, and Signaling

Nervous and Sensory Systems

Motor Mechanisms and Behavior

Population Ecology and the Distribution of Organisms

Species Interactions

Ecosystems and Energy

Global Ecology and Conservation Biology

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