Question 1

The functional group written as -COOH is called the _______ group.

Accepted Answer

The answer of The functional group written as -COOH is...

Question 2

Chemical modification of macromolecules

Accepted Answer

A)  affects structure, not function. 
B)  affects structure and function. 
C)  affects function, not structure. 
D)  occurs only in animals, not plants. 
E)  occurs only in plants, not animals. 
A)  affects structure, not function. 
B)  affects structure and function. 
C)  affects function, not structure. 
D)  occurs only in animals, not plants. 
E)  occurs only in plants, not animals.

Question 3

Under what conditions would a biologist be justified in stating that two newly discovered proteins-one isolated from a bacterium and the other isolated from a plant-must have identical properties and functions in the two different organisms?

Accepted Answer

The structure of a protein den

Question 4

Refer to the table below.   Which statement about amino acids 1 and 2 is valid, given all of the data provided in the table?

Accepted Answer

A)  They are identical in structure. 
B)  They have different R groups. 
C)  They are optical isomers. 
D)  They have opposite charges. 
E)  They contain different types of bonds. 
A)  They are identical in structure. 
B)  They have different R groups. 
C)  They are optical isomers. 
D)  They have opposite charges. 
E)  They contain different types of bonds.

Question 5

Molecular chaperones

Accepted Answer

A)  are small molecules present in the cytoplasm. 
B)  are made in lesser amounts after exposure of an organism to high temperatures. 
C)  are enzymes that add functional groups onto polypeptides. 
D)  can prevent harmful interactions caused by improperly folded proteins. 
E)  bind proteins irreversibly to denature them. 
A)  are small molecules present in the cytoplasm. 
B)  are made in lesser amounts after exposure of an organism to high temperatures. 
C)  are enzymes that add functional groups onto polypeptides. 
D)  can prevent harmful interactions caused by improperly folded proteins. 
E)  bind proteins irreversibly to denature them.

Question 6

A molecule that has an N-C-C repeat in its structure is classified as a

Accepted Answer

A)  carbohydrate. 
B)  lipid. 
C)  protein. 
D)  polysaccharide. 
E)  fat. 
A)  carbohydrate. 
B)  lipid. 
C)  protein. 
D)  polysaccharide. 
E)  fat.

Question 7

A molecule with the formula C15H30O15 is most likely a

Accepted Answer

A)  hydrocarbon. 
B)  carbohydrate. 
C)  lipid. 
D)  protein. 
E)  nucleic acid. 
A)  hydrocarbon. 
B)  carbohydrate. 
C)  lipid. 
D)  protein. 
E)  nucleic acid.

Question 8

People born with the genetic disorder known as glycogen storage disease have impaired glycogen synthase.Glycogen synthase is the protein that catalyzes the polymerization of glucose to form glycogen.Affected people exhibit extreme tiredness and poor muscle function upon developing very low blood sugar levels when they have not eaten in a while.They show improvements soon after taking in food, which boosts their blood sugar concentrations.If the cells of these patients cannot polymerize glucose into glycogen, why don't the cells simply store excess glucose monomers for use during times between meals?

Accepted Answer

A)  The accumulation of large numbers of glucose monomers would upset the osmotic balance of cells in a way that glycogen does not. 
B)  A large number of glucose monomers would take up much more space inside cells than glycogen made from an equivalent number of monomers. 
C)  Glucose monomers would have no way to move back across the cell membrane once they entered a cell. 
D)  The cells would immediately metabolize all of the glucose monomers, creating very large amounts of heat that would destroy the cells. 
E)  The large number of glucose monomers would begin reacting with other molecules in the cell, causing disruption of normal metabolic reactions. 
A)  The accumulation of large numbers of glucose monomers would upset the osmotic balance of cells in a way that glycogen does not. 
B)  A large number of glucose monomers would take up much more space inside cells than glycogen made from an equivalent number of monomers. 
C)  Glucose monomers would have no way to move back across the cell membrane once they entered a cell. 
D)  The cells would immediately metabolize all of the glucose monomers, creating very large amounts of heat that would destroy the cells. 
E)  The large number of glucose monomers would begin reacting with other molecules in the cell, causing disruption of normal metabolic reactions.

Question 9

Which statement about starch is false?

Accepted Answer

A)  It may be partially branched. 
B)  It is a polymer of glucose. 
C)  It is formed by the condensation of monomers. 
D)  It has properties very similar to those of cellulose. 
E)  It can be digested by humans. 
A)  It may be partially branched. 
B)  It is a polymer of glucose. 
C)  It is formed by the condensation of monomers. 
D)  It has properties very similar to those of cellulose. 
E)  It can be digested by humans.

Question 10

Refer to the table below summarizing data obtained from mutation experiments on a protein enzyme.   Specific amino acid substitutions were made at residue 107, which is occupied by a serine residue in the normal protein.After the mutant proteins were made and purified, their enzymatic activities were measured and expressed as a percentage of unmutated protein's enzyme activity.Which statement provides the most plausible explanation of why such widely different changes in activity of the enzyme were observed?

Accepted Answer

A)  Some mutations lead to disruption of an important salt bridge in the protein, while others do not. 
B)  Some mutations insert hydrophilic residues into a hydrophobic region of the protein, while others do not. 
C)  Some mutations insert very large residues into a region of the protein that can accommodate only small side chains, while others do not. 
D)  Some mutations remove a hydroxyl group in the side chain of residue 107, while others do not. 
E)  Some mutations replace a hydroxyl group with a basic group, while others replace a hydroxyl group with an acidic group. 
A)  Some mutations lead to disruption of an important salt bridge in the protein, while others do not. 
B)  Some mutations insert hydrophilic residues into a hydrophobic region of the protein, while others do not. 
C)  Some mutations insert very large residues into a region of the protein that can accommodate only small side chains, while others do not. 
D)  Some mutations remove a hydroxyl group in the side chain of residue 107, while others do not. 
E)  Some mutations replace a hydroxyl group with a basic group, while others replace a hydroxyl group with an acidic group.

Question 11

A simple sugar with the formula C5H10O5 can be classified as a

Accepted Answer

A)  hexose. 
B)  polysaccharide. 
C)  disaccharide. 
D)  pentose. 
E)  lipid. 
A)  hexose. 
B)  polysaccharide. 
C)  disaccharide. 
D)  pentose. 
E)  lipid.

Question 12

Refer to the figures below.   The two pairs of molecules represent different types of isomers.Identify each type and explain how these types are similar and how they differ.

Accepted Answer

Pair 1 represents a pair of cis-trans is

Question 13

Glycogen molecules can vary greatly in size, yet all glycogen molecules perform the same function.Proteins can also vary greatly in size; however, proteins also vary greatly in function.Which statement best explains this difference between glycogen and proteins?

Accepted Answer

A)  Glycosidic bonds link the monomers that make up glycogen, whereas peptide bonds link the monomers that make up proteins. 
B)  The monomers making up glycogen are characterized by their many hydroxyl (-OH) groups, whereas the monomers making up proteins are characterized by their amino (NH2) and carboxyl (COOH) groups. 
C)  Glycogen molecules are highly branched in structure, whereas proteins consist of long, unbranched polymer chains. 
D)  Glycogen molecules are composed of one type of monomer, whereas proteins consist of twenty different monomers with different properties. 
E)  The monomers making up glycogen can convert between ring structures and straight-chain forms, whereas the monomers making up proteins do not undergo these changes. 
A)  Glycosidic bonds link the monomers that make up glycogen, whereas peptide bonds link the monomers that make up proteins. 
B)  The monomers making up glycogen are characterized by their many hydroxyl (-OH) groups, whereas the monomers making up proteins are characterized by their amino (NH2) and carboxyl (COOH) groups. 
C)  Glycogen molecules are highly branched in structure, whereas proteins consist of long, unbranched polymer chains. 
D)  Glycogen molecules are composed of one type of monomer, whereas proteins consist of twenty different monomers with different properties. 
E)  The monomers making up glycogen can convert between ring structures and straight-chain forms, whereas the monomers making up proteins do not undergo these changes.

Question 14

The shape of a folded protein is determined by

Accepted Answer

A)  its tertiary structure. 
B)  the sequence of its amino acids. 
C)  whether the peptide bonds have F1F1F1S1F1F1F10 or F1F1F1S1F1F1F10 linkages. 
D)  the number of peptide bonds. 
E)  the base-pairing rules. 
A)  its tertiary structure. 
B)  the sequence of its amino acids. 
C)  whether the peptide bonds have F1F1F1S1F1F1F10 or F1F1F1S1F1F1F10 linkages. 
D)  the number of peptide bonds. 
E)  the base-pairing rules.

Question 15

Refer to the figure below.   How does the molecule shown differ from a triglyceride?

Accepted Answer

A)  It is less polar. 
B)  It is not classified as a lipid. 
C)  It is amphipathic. 
D)  It contains glycerol in its structure. 
E)  It contains ester linkages. 
A)  It is less polar. 
B)  It is not classified as a lipid. 
C)  It is amphipathic. 
D)  It contains glycerol in its structure. 
E)  It contains ester linkages.

Question 16

van der Waals forces can form between _______ side chains in proteins.

Accepted Answer

The answer of van der Waals forces can form between...

Question 17

A protein is known to be stabilized by a salt bridge between a lysine at position 26 and an aspartic acid at position 108 in the protein's amino acid sequence.When the protein is mutated to substitute a glutamic acid in place of aspartic acid at position 108, the protein cannot fold properly and exhibits no biological activity.What likely contributes to the effects of this amino acid substitution on protein folding?

Accepted Answer

Glutamic acid would provide the necessar

Question 18

The reactive _______ contributes to the ability of aldehydes and ketones to be involved in energy reactions.

Accepted Answer

A)  phosphate 
B)  carbonyl 
C)  sulfur 
D)  R group 
E)  nitrogen 
A)  phosphate 
B)  carbonyl 
C)  sulfur 
D)  R group 
E)  nitrogen

Question 19

Due to its six hydroxyl groups attached to its six-carbon backbone, the carbohydrate compound inositol can be classified as a(n) _______.

Accepted Answer

The answer of Due to its six hydroxyl groups attached...

Question 20

In an alpha helix, the coiling is stabilized by

Accepted Answer

A)  the hydrophobic nature of the R chains, which causes the chain to coil with the R groups inward. 
B)  hydrogen bonding of the N-H groups on one amino acid and the C=O groups on another. 
C)  repulsion of the R chains from each other, causing the coil to form with the R groups on the outside. 
D)  disulfide bond formation between cysteines that are regularly spaced along peptide chains. 
E)  the N-C-C repeat of the peptide backbone, allowing for regularly spaced peptide bonds between chain segments. 
A)  the hydrophobic nature of the R chains, which causes the chain to coil with the R groups inward. 
B)  hydrogen bonding of the N-H groups on one amino acid and the C=O groups on another. 
C)  repulsion of the R chains from each other, causing the coil to form with the R groups on the outside. 
D)  disulfide bond formation between cysteines that are regularly spaced along peptide chains. 
E)  the N-C-C repeat of the peptide backbone, allowing for regularly spaced peptide bonds between chain segments.

Exam 3: Proteins, Carbohydrates, and Lipids

The functional group written as -COOH is called the _______ group.

Chemical modification of macromolecules

Under what conditions would a biologist be justified in stating that two newly discovered proteins-one isolated from a bacterium and the other isolated from a plant-must have identical properties and functions in the two different organisms?

Refer to the table below. Which statement about amino acids 1 and 2 is valid, given all of the data provided in the table?

Molecular chaperones

A molecule that has an N-C-C repeat in its structure is classified as a

A molecule with the formula C15H30O15 is most likely a

Which statement about starch is false?

A simple sugar with the formula C5H10O5 can be classified as a

Refer to the figures below. The two pairs of molecules represent different types of isomers.Identify each type and explain how these types are similar and how they differ.

Glycogen molecules can vary greatly in size, yet all glycogen molecules perform the same function.Proteins can also vary greatly in size; however, proteins also vary greatly in function.Which statement best explains this difference between glycogen and proteins?

The shape of a folded protein is determined by

Refer to the figure below. How does the molecule shown differ from a triglyceride?

van der Waals forces can form between _______ side chains in proteins.

The reactive _______ contributes to the ability of aldehydes and ketones to be involved in energy reactions.

Due to its six hydroxyl groups attached to its six-carbon backbone, the carbohydrate compound inositol can be classified as a(n) _______.

In an alpha helix, the coiling is stabilized by

Studying Life

Small Molecules and the Chemistry of Life

Nucleic Acids and the Origin of Life

Cells: the Working Units of Life

Cell Membranes

Cell Communication and Multicellularity

Energy, Enzymes, and Metabolism

Pathways That Harvest Chemical Energy

Photosynthesis: Energy From Sunlight

The Cell Cycle and Cell Division

Inheritance, Genes, and Chromosomes

Dna and Its Role in Heredity

From Dna to Protein: Gene Expression

Gene Mutation and Molecular Medicine

Regulation of Gene Expression

Genomes

Recombinant Dna and Biotechnology

Mechanisms of Evolution

Reconstructing and Using Phylogenies

Speciation

Evolution of Genes and Genomes

The History of Life on Earth

Bacteria, Archaea, and Viruses

The Origin and Diversification of Eukaryotes

Plants Without Seeds: From Water to Land

The Evolution of Seed Plants

The Evolution and Diversity of Fungi

Animal Origins and the Evolution of Body Plans

Protostome Animals

Deuterostome Animals

The Plant Body

Transport in Plants

Plant Nutrition

Regulation of Plant Growth

Reproduction in Flowering Plants

Plant Responses to Environmental Challenges

Physiology, Homeostasis, and Temperature Regulation

Animal Hormones

Immunology: Animal Defense Systems

Animal Reproduction

Animal Development

Neurons, Glia, and Nervous Systems

Sensory Systems

The Mammalian Nervous System: Structure and Higher Functions

Musculoskeletal Systems

Gas Exchange

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Salt and Water Balance and Nitrogen Excretion

Animal Behavior

The Physical Environment and Biogeography of Life

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A Changing Biosphere

Filters

A molecule with the formula C₁₅H₃₀O₁₅ is most likely a

A simple sugar with the formula C₅H₁₀O₅ can be classified as a