Question 1

How many structural isomers are possible for a substance having the molecular formula C₄H₁₀?

Accepted Answer

A)  1 
B)  2 
C)  4 
D)  3 
E)  11 
A)  1 
B)  2 
C)  4 
D)  3 
E)  11

Question 2

-Which molecule shown above can form a dimer linked by a covalent bond?

Accepted Answer

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

Question 3

-Which molecule shown above is a thiol?

Accepted Answer

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

Question 4

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 one another. 
C)  exist in either linear chain or ring forms. 
D)  differ in the location of their double bonds. 
E)  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 one another. 
C)  exist in either linear chain or ring forms. 
D)  differ in the location of their double bonds. 
E)  differ in the arrangement of atoms around their double bonds.

Question 5

Which of the following statements best describes the carbon atoms present in a seed-eating bird?

Accepted Answer

A)  Inorganic carbon atoms in the seeds were incorporated into organic molecules by the bird. 
B)  The carbon atoms ultimately came from the soil. 
C)  The carbon atoms are ultimately derived from coal. 
D)  The carbon atoms ultimately came from carbon dioxide incorporated into sugars through photosynthesis. 
E)  The carbon atoms ultimately came from simple organic compounds that formed abiotically from inorganic carbon, hydrogen, oxygen, and nitrogen atoms. 
A)  Inorganic carbon atoms in the seeds were incorporated into organic molecules by the bird. 
B)  The carbon atoms ultimately came from the soil. 
C)  The carbon atoms are ultimately derived from coal. 
D)  The carbon atoms ultimately came from carbon dioxide incorporated into sugars through photosynthesis. 
E)  The carbon atoms ultimately came from simple organic compounds that formed abiotically from inorganic carbon, hydrogen, oxygen, and nitrogen atoms.

Question 6

A carbon skeleton is covalently bonded to both an amino group and a carboxyl group. When placed in water it

Accepted Answer

A)  would function only as an acid because of the carboxyl group. 
B)  would function only as a base because of the amino group. 
C)  would function as neither an acid nor a base. 
D)  would function as both an acid and a base. 
E)  is impossible to determine how it would function. 
A)  would function only as an acid because of the carboxyl group. 
B)  would function only as a base because of the amino group. 
C)  would function as neither an acid nor a base. 
D)  would function as both an acid and a base. 
E)  is impossible to determine how it would function.

Question 7

Compared to a hydrocarbon chain where all the carbon atoms are linked by single bonds, a hydrocarbon chain with the same number of carbon atoms, but with one or more double bonds, will

Accepted Answer

A)  be more flexible in structure. 
B)  be more constrained in structure. 
C)  be more polar. 
D)  have more hydrogen atoms. 
E)  have fewer structurally distinct isomers. 
A)  be more flexible in structure. 
B)  be more constrained in structure. 
C)  be more polar. 
D)  have more hydrogen atoms. 
E)  have fewer structurally distinct isomers.

Question 8

Stanley Miller's 1953 experiments proved that

Accepted Answer

A)  life arose on Earth from simple inorganic molecules. 
B)  organic molecules can be synthesized abiotically under conditions that may have existed on early Earth. 
C)  life arose on Earth from simple organic molecules, with energy from lightning and volcanoes. 
D)  the conditions on early Earth were conducive to the origin of life. 
E)  the conditions on early Earth were conducive to the abiotic synthesis of organic molecules. 
A)  life arose on Earth from simple inorganic molecules. 
B)  organic molecules can be synthesized abiotically under conditions that may have existed on early Earth. 
C)  life arose on Earth from simple organic molecules, with energy from lightning and volcanoes. 
D)  the conditions on early Earth were conducive to the origin of life. 
E)  the conditions on early Earth were conducive to the abiotic synthesis of organic molecules.

Question 9

-Which pair of molecules shown below are not enantiomers of a single molecule?

Accepted Answer

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

Question 10

Which of the following hydrocarbons has a double bond in its carbon skeleton?

Accepted Answer

A)  C₃H₈ 
B)  C₂H₆ 
C)  CH₄ 
D)  C₂H₄ 
E)  C₂H₂ 
A)  C₃H₈ 
B)  C₂H₆ 
C)  CH₄ 
D)  C₂H₄ 
E)  C₂H₂

Question 11

A chemist wishes to make an organic molecule less acidic. Which of the following functional groups should be added to the molecule in order to do so?

Accepted Answer

A)  carboxyl 
B)  sulfhydryl 
C)  hydroxyl 
D)  amino 
E)  phosphate 
A)  carboxyl 
B)  sulfhydryl 
C)  hydroxyl 
D)  amino 
E)  phosphate

Question 12

Which functional group is not present in this molecule?

Accepted Answer

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

Question 13

A compound contains hydroxyl groups as its predominant functional group. Which of the following statements is true concerning this compound?

Accepted Answer

A)  It lacks an asymmetric carbon, and it is probably a fat or lipid. 
B)  It should dissolve in water. 
C)  It should dissolve in a nonpolar solvent. 
D)  It won't form hydrogen bonds with water. 
E)  It is hydrophobic. 
A)  It lacks an asymmetric carbon, and it is probably a fat or lipid. 
B)  It should dissolve in water. 
C)  It should dissolve in a nonpolar solvent. 
D)  It won't form hydrogen bonds with water. 
E)  It is hydrophobic.

Question 14

The complexity and variety of organic molecules is due to

Accepted Answer

A)  the chemical versatility of carbon atoms. 
B)  the variety of rare elements in organic molecules. 
C)  the fact that they can be synthesized only in living organisms. 
D)  their interaction with water. 
E)  their tremendously large sizes. 
A)  the chemical versatility of carbon atoms. 
B)  the variety of rare elements in organic molecules. 
C)  the fact that they can be synthesized only in living organisms. 
D)  their interaction with water. 
E)  their tremendously large sizes.

Question 15

Organic molecules with only hydrogens and five carbon atoms can have different structures in all of the following ways except

Accepted Answer

A)  by branching of the carbon skeleton. 
B)  by varying the number of double bonds between carbon atoms. 
C)  by varying the position of double bonds between carbon atoms. 
D)  by forming a ring. 
E)  by forming enantiomers. 
A)  by branching of the carbon skeleton. 
B)  by varying the number of double bonds between carbon atoms. 
C)  by varying the position of double bonds between carbon atoms. 
D)  by forming a ring. 
E)  by forming enantiomers.

Question 16

-Three or four of the following illustrations depict different structural isomers of the organic compound with molecular formula C₆H₁₄. For clarity, only the carbon skeletons are shown; hydrogen atoms that would be attached to the carbons have been omitted. Which one, if any, is NOT a structural isomer of this compound?

Accepted Answer

A)    
B)    
C)    
D)    
E)  Each of the illustrations in the other answer choices depicts a structural isomer of the compound with molecular formula C₆H₁₄. 
A)    
B)    
C)    
D)    
E)  Each of the illustrations in the other answer choices depicts a structural isomer of the compound with molecular formula C₆H₁₄.

Question 17

Amino acids are acids because they always possess which functional group?

Accepted Answer

A)  amino 
B)  carbonyl 
C)  carboxyl 
D)  phosphate 
E)  hydroxyl 
A)  amino 
B)  carbonyl 
C)  carboxyl 
D)  phosphate 
E)  hydroxyl

Question 18

Why are hydrocarbons insoluble in water?

Accepted Answer

A)  The majority of their bonds are polar covalent carbon-to-hydrogen linkages. 
B)  The majority of their bonds are nonpolar covalent carbon-to-hydrogen linkages. 
C)  They are hydrophilic. 
D)  They exhibit considerable molecular complexity and diversity. 
E)  They are lighter than water. 
A)  The majority of their bonds are polar covalent carbon-to-hydrogen linkages. 
B)  The majority of their bonds are nonpolar covalent carbon-to-hydrogen linkages. 
C)  They are hydrophilic. 
D)  They exhibit considerable molecular complexity and diversity. 
E)  They are lighter than water.

Question 19

Which of the following statements best describes the carbon atoms present in a seed-eating bird?

Accepted Answer

A)  They were incorporated into organic molecules by plants. 
B)  They were processed into sugars through photosynthesis. 
C)  They are ultimately derived from carbon dioxide. 
D)  They were incorporated into organic molecules by plants, and they are ultimately derived from carbon dioxide. 
E)  They were incorporated into organic molecules by plants, they were processed into sugars through photosynthesis, and they are ultimately derived from carbon dioxide. 
A)  They were incorporated into organic molecules by plants. 
B)  They were processed into sugars through photosynthesis. 
C)  They are ultimately derived from carbon dioxide. 
D)  They were incorporated into organic molecules by plants, and they are ultimately derived from carbon dioxide. 
E)  They were incorporated into organic molecules by plants, they were processed into sugars through photosynthesis, and they are ultimately derived from carbon dioxide.

Question 20

-Which of the groups above is a carboxyl functional group?

Accepted Answer

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

Exam 4: Carbon and the Molecular Diversity of Life

How many structural isomers are possible for a substance having the molecular formula C₄H₁₀?

-Which molecule shown above can form a dimer linked by a covalent bond?

-Which molecule shown above is a thiol?

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

Which of the following statements best describes the carbon atoms present in a seed-eating bird?

A carbon skeleton is covalently bonded to both an amino group and a carboxyl group. When placed in water it

Compared to a hydrocarbon chain where all the carbon atoms are linked by single bonds, a hydrocarbon chain with the same number of carbon atoms, but with one or more double bonds, will

Stanley Miller's 1953 experiments proved that

-Which pair of molecules shown below are not enantiomers of a single molecule?

Which of the following hydrocarbons has a double bond in its carbon skeleton?

A chemist wishes to make an organic molecule less acidic. Which of the following functional groups should be added to the molecule in order to do so?

Which functional group is not present in this molecule?

A compound contains hydroxyl groups as its predominant functional group. Which of the following statements is true concerning this compound?

The complexity and variety of organic molecules is due to

Organic molecules with only hydrogens and five carbon atoms can have different structures in all of the following ways except

Amino acids are acids because they always possess which functional group?

Why are hydrocarbons insoluble in water?

Which of the following statements best describes the carbon atoms present in a seed-eating bird?

-Which of the groups above is a carboxyl functional group?

Introduction: Themes in the Study of Life

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

From Gene to Protein

Regulation of Gene Expression

Viruses

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

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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