Question 1

Which level of protein structure do the α helix and the β pleated sheet represent?

Accepted Answer

A)  primary 
B)  secondary 
C)  tertiary 
D)  quaternary 
E)  primary, secondary, tertiary, and quaternary 
A)  primary 
B)  secondary 
C)  tertiary 
D)  quaternary 
E)  primary, secondary, tertiary, and quaternary

Question 2

How will brief heating (to 95°C)affect macromolecular structures in aqueous solution?

Accepted Answer

A)  DNA duplexes will unwind and separate. 
B)  Proteins will unfold (denature). 
C)  Starch will hydrolyze into monomeric sugars. 
D)  Proteins will hydrolyze into amino acids. 
E)  DNA duplexes will unwind and separate, and proteins will unfold (denature). 
A)  DNA duplexes will unwind and separate. 
B)  Proteins will unfold (denature). 
C)  Starch will hydrolyze into monomeric sugars. 
D)  Proteins will hydrolyze into amino acids. 
E)  DNA duplexes will unwind and separate, and proteins will unfold (denature).

Question 3

The following questions are based on the 15 molecules illustrated in Figure 5.8. Each molecule may be used once, more than once, or not at all.
   
Figure 5.8
-Which of the following statements is false?

Accepted Answer

A)  Molecules 1 and 4 could be joined together by a glycosidic linkage to form a disaccharide. 
B)  Molecules 9 and 10 could be joined together by ester bonds to form a triacylglycerol. 
C)  Molecules 2 and 7 could be joined together to form a short peptide. 
D)  Molecules 2, 7, and 8 could be joined together to form a short peptide. 
E)  Molecules 14 and 15 could be joined together to form a polypeptide. 
A)  Molecules 1 and 4 could be joined together by a glycosidic linkage to form a disaccharide. 
B)  Molecules 9 and 10 could be joined together by ester bonds to form a triacylglycerol. 
C)  Molecules 2 and 7 could be joined together to form a short peptide. 
D)  Molecules 2, 7, and 8 could be joined together to form a short peptide. 
E)  Molecules 14 and 15 could be joined together to form a polypeptide.

Question 4

Which of the following is true of both starch and cellulose?

Accepted Answer

A)  They are both polymers of glucose. 
B)  They are cis-trans isomers of each other. 
C)  They can both be digested by humans. 
D)  They are both used for energy storage in plants. 
E)  They are both structural components of the plant cell wall. 
A)  They are both polymers of glucose. 
B)  They are cis-trans isomers of each other. 
C)  They can both be digested by humans. 
D)  They are both used for energy storage in plants. 
E)  They are both structural components of the plant cell wall.

Question 5

How many different kinds of polypeptides, each composed of 12 amino acids, could be synthesized using the 20 common amino acids?

Accepted Answer

A)  4¹² 
B)  12²⁰ 
C)  240 
D)  20 
E)  20¹² 
A)  4¹² 
B)  12²⁰ 
C)  240 
D)  20 
E)  20¹²

Question 6

What aspects of protein structure are stabilized or assisted by hydrogen bonds?

Accepted Answer

A)  primary structure 
B)  secondary structure 
C)  tertiary structure 
D)  quaternary structure 
E)  secondary, tertiary, and quaternary structures, but not primary structure 
A)  primary structure 
B)  secondary structure 
C)  tertiary structure 
D)  quaternary structure 
E)  secondary, tertiary, and quaternary structures, but not primary structure

Question 7

The R group or side chain of the amino acid serine is -CH₂-OH. The R group or side chain of the amino acid leucine is -CH₂-CH-(CH₃)₂. Where would you expect to find these amino acids in a globular protein in aqueous solution?

Accepted Answer

A)  Serine would be in the interior, and leucine would be on the exterior of the globular protein. 
B)  Leucine would be in the interior, and serine would be on the exterior of the globular protein. 
C)  Both serine and leucine would be in the interior of the globular protein. 
D)  Both serine and leucine would be on the exterior of the globular protein. 
E)  Both serine and leucine would be in the interior and on the exterior of the globular protein. 
A)  Serine would be in the interior, and leucine would be on the exterior of the globular protein. 
B)  Leucine would be in the interior, and serine would be on the exterior of the globular protein. 
C)  Both serine and leucine would be in the interior of the globular protein. 
D)  Both serine and leucine would be on the exterior of the globular protein. 
E)  Both serine and leucine would be in the interior and on the exterior of the globular protein.

Question 8

Which of the following is true regarding saturated fatty acids?

Accepted Answer

A)  They are the predominant fatty acid in corn oil. 
B)  They have double bonds between carbon atoms of the fatty acids. 
C)  They are the principal molecules in lard and butter. 
D)  They are usually liquid at room temperature. 
E)  They are usually produced by plants. 
A)  They are the predominant fatty acid in corn oil. 
B)  They have double bonds between carbon atoms of the fatty acids. 
C)  They are the principal molecules in lard and butter. 
D)  They are usually liquid at room temperature. 
E)  They are usually produced by plants.

Question 9

Which of the following is not a monomer/polymer pairing?

Accepted Answer

A)  monosaccharide/polysaccharide 
B)  amino acid/protein 
C)  triglyceride/phospholipid bilayer 
D)  deoxyribonucleotide/DNA 
E)  ribonucleotide/RNA 
A)  monosaccharide/polysaccharide 
B)  amino acid/protein 
C)  triglyceride/phospholipid bilayer 
D)  deoxyribonucleotide/DNA 
E)  ribonucleotide/RNA

Question 10

Figure 5.2
-Which of the following statements is true regarding the molecule illustrated in Figure 5.2?

Accepted Answer

A)  It is a saturated fatty acid. 
B)  A diet rich in this molecule may contribute to atherosclerosis. 
C)  Molecules of this type are usually liquid at room temperature. 
D)  It is a saturated fatty acid and a diet rich in this molecule may contribute to atherosclerosis. 
E)  It is a saturated fatty acid, a diet rich in this molecule may contribute to atherosclerosis, and molecules of this type are usually liquid at room temperature. 
A)  It is a saturated fatty acid. 
B)  A diet rich in this molecule may contribute to atherosclerosis. 
C)  Molecules of this type are usually liquid at room temperature. 
D)  It is a saturated fatty acid and a diet rich in this molecule may contribute to atherosclerosis. 
E)  It is a saturated fatty acid, a diet rich in this molecule may contribute to atherosclerosis, and molecules of this type are usually liquid at room temperature.

Question 11

At which level of protein structure are interactions between the side chains (R groups)most important?

Accepted Answer

A)  primary 
B)  secondary 
C)  tertiary 
D)  quaternary 
E)  all of the above 
A)  primary 
B)  secondary 
C)  tertiary 
D)  quaternary 
E)  all of the above

Question 12

DNAase is an enzyme that catalyzes the hydrolysis of the covalent bonds that join nucleotides together. What would first happen to DNA molecules treated with DNAase?

Accepted Answer

A)  The two strands of the double helix would separate. 
B)  The phosphodiester bonds between deoxyribose sugars would be broken. 
C)  The purines would be separated from the deoxyribose sugars. 
D)  The pyrimidines would be separated from the deoxyribose sugars. 
E)  All bases would be separated from the deoxyribose sugars. 
A)  The two strands of the double helix would separate. 
B)  The phosphodiester bonds between deoxyribose sugars would be broken. 
C)  The purines would be separated from the deoxyribose sugars. 
D)  The pyrimidines would be separated from the deoxyribose sugars. 
E)  All bases would be separated from the deoxyribose sugars.

Question 13

Refer to Figure 5.6 to answer the following questions.
   
Figure 5.6
-Which bond is a peptide bond?

Accepted Answer

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

Question 14

Humans can digest starch but not cellulose because

Accepted Answer

A)  the monomer of starch is glucose, while the monomer of cellulose is galactose. 
B)  humans have enzymes that can hydrolyze the β glycosidic linkages of starch but not the α glycosidic linkages of cellulose. 
C)  humans have enzymes that can hydrolyze the α glycosidic linkages of starch but not the β glycosidic linkages of cellulose. 
D)  humans harbor starch-digesting bacteria in the digestive tract. 
E)  the monomer of starch is glucose, while the monomer of cellulose is glucose with a nitrogen-containing group. 
A)  the monomer of starch is glucose, while the monomer of cellulose is galactose. 
B)  humans have enzymes that can hydrolyze the β glycosidic linkages of starch but not the α glycosidic linkages of cellulose. 
C)  humans have enzymes that can hydrolyze the α glycosidic linkages of starch but not the β glycosidic linkages of cellulose. 
D)  humans harbor starch-digesting bacteria in the digestive tract. 
E)  the monomer of starch is glucose, while the monomer of cellulose is glucose with a nitrogen-containing group.

Question 15

Which modifications of fatty acids will best keep triglycerides solid at warmer temperatures?

Accepted Answer

A)  creating cis double bonds to the fatty acids 
B)  adding hydrogens to the fatty acids 
C)  creating trans double bonds to the fatty acids 
D)  adding hydrogens and trans double bonds to the fatty acids 
E)  adding cis double bonds and trans double bonds to the fatty acids 
A)  creating cis double bonds to the fatty acids 
B)  adding hydrogens to the fatty acids 
C)  creating trans double bonds to the fatty acids 
D)  adding hydrogens and trans double bonds to the fatty acids 
E)  adding cis double bonds and trans double bonds to the fatty acids

Question 16

Refer to Figure 5.6 to answer the following questions.
   
Figure 5.6
-At which bond would water need to be added to achieve hydrolysis of the peptide, back to its component amino acid?

Accepted Answer

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

Question 17

Figure 5.3
-The molecule shown in Figure 5.3 is a

Accepted Answer

A)  polysaccharide. 
B)  polypeptide. 
C)  saturated fatty acid. 
D)  triacylglycerol. 
E)  unsaturated fatty acid. 
A)  polysaccharide. 
B)  polypeptide. 
C)  saturated fatty acid. 
D)  triacylglycerol. 
E)  unsaturated fatty acid.

Question 18

Normal hemoglobin is a tetramer, consisting of two molecules of β hemoglobin and two molecules of α hemoglobin. In sickle-cell disease, as a result of a single amino acid change, the mutant hemoglobin tetramers associate with each other and assemble into large fibers. Based on this information alone, we can conclude that sickle-cell hemoglobin exhibits

Accepted Answer

A)  altered primary structure. 
B)  altered secondary structure. 
C)  altered tertiary structure. 
D)  altered quaternary structure. 
E)  altered primary structure and altered quaternary structure; the secondary and tertiary structures may or may not be altered. 
A)  altered primary structure. 
B)  altered secondary structure. 
C)  altered tertiary structure. 
D)  altered quaternary structure. 
E)  altered primary structure and altered quaternary structure; the secondary and tertiary structures may or may not be altered.

Question 19

Polysaccharides, triacylglycerides, and proteins are similar in that they

Accepted Answer

A)  are synthesized from monomers by the process of hydrolysis. 
B)  are synthesized from subunits by dehydration reactions. 
C)  are synthesized as a result of peptide bond formation between monomers. 
D)  are decomposed into their subunits by dehydration reactions. 
E)  all contain nitrogen in their monomer building blocks. 
A)  are synthesized from monomers by the process of hydrolysis. 
B)  are synthesized from subunits by dehydration reactions. 
C)  are synthesized as a result of peptide bond formation between monomers. 
D)  are decomposed into their subunits by dehydration reactions. 
E)  all contain nitrogen in their monomer building blocks.

Question 20

The structural level of a protein least affected by a disruption in hydrogen bonding is the

Accepted Answer

A)  primary level. 
B)  secondary level. 
C)  tertiary level. 
D)  quaternary level. 
E)  All structural levels are equally affected. 
A)  primary level. 
B)  secondary level. 
C)  tertiary level. 
D)  quaternary level. 
E)  All structural levels are equally affected.

Exam 5: The Structure and Function of Large Biological Molecules

Which level of protein structure do the α helix and the β pleated sheet represent?

How will brief heating (to 95°C)affect macromolecular structures in aqueous solution?

The following questions are based on the 15 molecules illustrated in Figure 5.8. Each molecule may be used once, more than once, or not at all. Figure 5.8 -Which of the following statements is false?

Which of the following is true of both starch and cellulose?

How many different kinds of polypeptides, each composed of 12 amino acids, could be synthesized using the 20 common amino acids?

What aspects of protein structure are stabilized or assisted by hydrogen bonds?

The R group or side chain of the amino acid serine is -CH₂-OH. The R group or side chain of the amino acid leucine is -CH₂-CH-(CH₃)₂. Where would you expect to find these amino acids in a globular protein in aqueous solution?

Which of the following is true regarding saturated fatty acids?

Which of the following is not a monomer/polymer pairing?

Figure 5.2 -Which of the following statements is true regarding the molecule illustrated in Figure 5.2?

At which level of protein structure are interactions between the side chains (R groups)most important?

DNAase is an enzyme that catalyzes the hydrolysis of the covalent bonds that join nucleotides together. What would first happen to DNA molecules treated with DNAase?

Refer to Figure 5.6 to answer the following questions. Figure 5.6 -Which bond is a peptide bond?

Humans can digest starch but not cellulose because

Which modifications of fatty acids will best keep triglycerides solid at warmer temperatures?

Refer to Figure 5.6 to answer the following questions. Figure 5.6 -At which bond would water need to be added to achieve hydrolysis of the peptide, back to its component amino acid?

Figure 5.3 -The molecule shown in Figure 5.3 is a

Polysaccharides, triacylglycerides, and proteins are similar in that they

The structural level of a protein least affected by a disruption in hydrogen bonding is the

Introduction: Themes in the Study of Life

The Chemical Context of Life

Water and Life

Carbon and the Molecular Diversity of Life

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

Filters