Question 1

Use the figures to answer the question.

Which molecule has at least one carbon atom attached to three different chemical groups?

Accepted Answer

A)  A 
B)  B 
C)  D 
D)  A and B 
A)  A 
B)  B 
C)  D 
D)  A and B

Question 2

Testosterone and estradiol are male and female sex hormones, respectively, in many vertebrates. In what way(s)do these molecules differ from each other? Testosterone and estradiol ________.

Accepted Answer

A)  are structural isomers but have the same molecular formula 
B)  are cis-trans isomers but have the same molecular formula 
C)  have different functional groups attached to the same carbon skeleton 
D)  are enantiomers of the same organic molecule 
A)  are structural isomers but have the same molecular formula 
B)  are cis-trans isomers but have the same molecular formula 
C)  have different functional groups attached to the same carbon skeleton 
D)  are enantiomers of the same organic molecule

Question 3

Why is carbon so important in biology?

Accepted Answer

A)  It is a common element on Earth. 
B)  It has very little electronegativity, making it a good electron donor. 
C)  It bonds to only a few other elements. 
D)  It can form a variety of carbon skeletons and host functional groups. 
A)  It is a common element on Earth. 
B)  It has very little electronegativity, making it a good electron donor. 
C)  It bonds to only a few other elements. 
D)  It can form a variety of carbon skeletons and host functional groups.

Question 4

Some carbon skeletons have different numbers and locations of double bonds to ________.

Accepted Answer

A)  add molecular complexity and diversity that characterize living matter 
B)  be more flexible that makes the molecule stronger 
C)  stay in its liquid state 
D)  increase its solubility in water 
A)  add molecular complexity and diversity that characterize living matter 
B)  be more flexible that makes the molecule stronger 
C)  stay in its liquid state 
D)  increase its solubility in water

Question 5

The element present in all organic molecules is ________.

Accepted Answer

A)  hydrogen 
B)  oxygen 
C)  carbon 
D)  nitrogen 
A)  hydrogen 
B)  oxygen 
C)  carbon 
D)  nitrogen

Question 6

Organic molecules with only hydrogens and five carbon atoms cannot ________.

Accepted Answer

A)  have a branching carbon skeleton 
B)  have different combinations of double bonds between carbon atoms 
C)  have different positions of double bonds between carbon atoms 
D)  form enantiomers 
A)  have a branching carbon skeleton 
B)  have different combinations of double bonds between carbon atoms 
C)  have different positions of double bonds between carbon atoms 
D)  form enantiomers

Question 7

Which of the following carbon molecules does not have the bond angle of 109.5°?

Accepted Answer

A)  CH₄ 
B)  C₂H₄ 
C)  C₂H₆ 
D)  C₃H₈ 
A)  CH₄ 
B)  C₂H₄ 
C)  C₂H₆ 
D)  C₃H₈

Question 8

Differences among organisms are caused by differences in the ________.

Accepted Answer

A)  elemental composition from organism to organism 
B)  types and relative amounts of organic molecules synthesized by each organism 
C)  sizes of the organic molecules in each organism 
D)  types of inorganic compounds present in each organism 
A)  elemental composition from organism to organism 
B)  types and relative amounts of organic molecules synthesized by each organism 
C)  sizes of the organic molecules in each organism 
D)  types of inorganic compounds present in each organism

Question 9

Which of the following molecules is polar?
C₃H₇OHC₂H₅COOH

Accepted Answer

A)  C₃H₇OH and C₂H₅COOH are both polar molecules. 
B)  Neither C₂H₅COOH or C₃H₇OH is polar. 
C)  C₂H₅COOH is polar, but C₃H₇OH is not polar. 
D)  C₂H₅COOH is not polar, but C₃H₇OH is polar. 
A)  C₃H₇OH and C₂H₅COOH are both polar molecules. 
B)  Neither C₂H₅COOH or C₃H₇OH is polar. 
C)  C₂H₅COOH is polar, but C₃H₇OH is not polar. 
D)  C₂H₅COOH is not polar, but C₃H₇OH is polar.

Question 10

Use the figures to answer the question.
 
Which functional group shown can pick up protons and raise the pH of the surrounding solution?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
A)  A 
B)  B 
C)  C 
D)  D

Question 11

Which of the following is true of carbon?

Accepted Answer

A)  It forms only polar molecules. 
B)  It can form a maximum of three covalent bonds with other elements. 
C)  It is highly electronegative. 
D)  It can form both polar and nonpolar bonds. 
A)  It forms only polar molecules. 
B)  It can form a maximum of three covalent bonds with other elements. 
C)  It is highly electronegative. 
D)  It can form both polar and nonpolar bonds.

Question 12

Use the figure to answer the question.
 
What is the name of the functional group shown in the figure?

Accepted Answer

A)  carbonyl 
B)  ketone 
C)  aldehyde 
D)  carboxyl 
A)  carbonyl 
B)  ketone 
C)  aldehyde 
D)  carboxyl

Question 13

Use the following figure to answer the question.
 
The two molecules shown in the figure are best described as ________.

Accepted Answer

A)  enantiomers 
B)  radioactive isotopes 
C)  structural isomers 
D)  cis-trans isomers 
A)  enantiomers 
B)  radioactive isotopes 
C)  structural isomers 
D)  cis-trans isomers

Question 14

Use the following figure to answer the question.
 
The figure shows the structures of glucose and fructose. These two molecules differ in the ________.

Accepted Answer

A)  number of carbon, hydrogen, and oxygen atoms 
B)  types of carbon, hydrogen, and oxygen atoms 
C)  arrangement of carbon, hydrogen, and oxygen atoms 
D)  number of oxygen atoms joined to carbon atoms by double covalent bonds 
A)  number of carbon, hydrogen, and oxygen atoms 
B)  types of carbon, hydrogen, and oxygen atoms 
C)  arrangement of carbon, hydrogen, and oxygen atoms 
D)  number of oxygen atoms joined to carbon atoms by double covalent bonds

Question 15

Which of the functional groups is not reactive but serves as a recognizable tag on the DNA molecule and alter the expression of genes in the cells.

Accepted Answer

A)  amino 
B)  methyl 
C)  carboxyl 
D)  hydroxyl 
A)  amino 
B)  methyl 
C)  carboxyl 
D)  hydroxyl

Question 16

Which of the following illustrations is not a structural isomer of an organic compound with the molecular formula C₆H₁₄? For clarity, only the carbon skeletons are shown; hydrogen atoms that would be attached to the carbons have been omitted.

Accepted Answer

A)    
B)    
C)    
D)    
A)    
B)    
C)    
D)

Question 17

How many electrons does one atom of carbon share to complete its valence shell?

Accepted Answer

A)  2 
B)  3 
C)  4 
D)  8 
A)  2 
B)  3 
C)  4 
D)  8

Question 18

Research indicates that ibuprofen, a drug used to relieve inflammation and pain, is a mixture of two enantiomers; that is, molecules that ________.

Accepted Answer

A)  have identical chemical formulas but differ in the branching of their carbon skeletons 
B)  are mirror images of each other 
C)  differ in the location of their double bonds 
D)  differ in the arrangement of atoms around their double bonds 
A)  have identical chemical formulas but differ in the branching of their carbon skeletons 
B)  are mirror images of each other 
C)  differ in the location of their double bonds 
D)  differ in the arrangement of atoms around their double bonds

Exam 4: Carbon and the Molecular Diversity of Life

Use the figures to answer the question. Which molecule has at least one carbon atom attached to three different chemical groups?

Testosterone and estradiol are male and female sex hormones, respectively, in many vertebrates. In what way(s)do these molecules differ from each other? Testosterone and estradiol ________.

Why is carbon so important in biology?

Some carbon skeletons have different numbers and locations of double bonds to ________.

The element present in all organic molecules is ________.

Organic molecules with only hydrogens and five carbon atoms cannot ________.

Which of the following carbon molecules does not have the bond angle of 109.5°?

Differences among organisms are caused by differences in the ________.

Which of the following molecules is polar? C₃H₇OHC₂H₅COOH

Use the figures to answer the question. Which functional group shown can pick up protons and raise the pH of the surrounding solution?

Which of the following is true of carbon?

Use the figure to answer the question. What is the name of the functional group shown in the figure?

Use the following figure to answer the question. The two molecules shown in the figure are best described as ________.

Use the following figure to answer the question. The figure shows the structures of glucose and fructose. These two molecules differ in the ________.

Which of the functional groups is not reactive but serves as a recognizable tag on the DNA molecule and alter the expression of genes in the cells.

Which of the following illustrations is not a structural isomer of an organic compound with the molecular formula C₆H₁₄? For clarity, only the carbon skeletons are shown; hydrogen atoms that would be attached to the carbons have been omitted.

How many electrons does one atom of carbon share to complete its valence shell?

Research indicates that ibuprofen, a drug used to relieve inflammation and pain, is a mixture of two enantiomers; that is, molecules that ________.

Evolution, the Themes of Biology, and Scientific Inquiry

The Chemical Context of Life

Water and Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Cell Communication

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

Viruses

DNA Tools and Biotechnology

Genomes and Their Evolution

Descent with Modification: A Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity II: The Evolution of Seed Plants

Fungi

An Overview of Animal Diversity

An Introduction to Invertebrates

The Origin and Evolution of Vertebrates

Vascular Plant Structure, Growth, and Development

Resource Acquisition and Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons, Synapses, and Signaling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behavior

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems and Restoration Ecology

Conservation Biology and Global Change

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