Question 1

Which of the following is a property of water that results from hydrogen bonding?

Accepted Answer

A)   The temperature of water changes very quickly.
B)   Many nonpolar substances dissolve in water.
C)   Water molecules are cohesive.
D)   Water is densest at 0°C.
E)   Water has a low surface tension.F) A) and B)
G) B) and D)

Question 2

Organic molecules

Accepted Answer

A)   always contain carbon.
B)   always contain hydrogen.
C)   always contain carbon and hydrogen.
D)   are found only in organisms, hence their name.
E)   are always food molecules.F) None of the above
G) C) and E)

Question 3

Which statement about DNA and RNA is correct?

Accepted Answer

A)   DNA is single-stranded, and RNA is double-stranded.
B)   The sugar in DNA is ribose, and in RNA the sugar is deoxyribose.
C)   RNA has a helix shape; DNA does not.
D)   The base uracil is unique to RNA and the base thymine unique to DNA.
E)   DNA is a nucleotide polymer while RNA is a carbohydrate polymer.F) C) and D)
G) All of the above

Question 4

________ is a polysaccharide that is found in plant cell walls and accounts for their strength.

Accepted Answer

A)   Cellulose
B)   Chitin
C)   Glycogen
D)   Starch
E)   CholesterolF) B) and E)
G) C) and D)

Question 5

The lower the pH

Accepted Answer

A)   the lower the hydrogen ion (H+)  concentration.
B)   the more acidic the solution.
C)   the higher the pH.
D)   the greater the hydroxide ion (OH-)  concentration.
E)   the closer the hydroxide ion (OH-)  concentration comes to equaling the hydrogen ion (H+)  concentration.F) D) and E)
G) A) and E)

Question 6

What type of reaction is necessary to produce a dipeptide from individual amino acids?

Accepted Answer

A)   dehydration reaction
B)   hydrolysis reaction
C)   denaturation
D)   Dipeptides are not formed from amino acids.
E)   None of the answer choices will form a dipeptide.F) C) and D)
G) B) and D)

Question 7

Potassium hydroxide (KOH)  almost completely dissociates in aqueous solution into K+ and OH-, which means it is a(n)

Accepted Answer

A)   acid.
B)   base.
C)   has no effect on pH.
D)   polar covalent molecule.
E)   nonpolar covalent molecule.F) A) and E)
G) A) and C)

Question 8

Which type of bond formation is responsible for the properties of lipids?

Accepted Answer

A)   hydrogen
B)   polar covalent
C)   ionic
D)   nonpolar covalent
E)   None of these bonds plays a role in the properties of water.F) A) and C)
G) A) and D) D

Question 9

The atomic mass of an element

Accepted Answer

A)   is determined by the number of protons and neutrons contained in the nucleus.
B)   equals the number of protons plus the number of electrons.
C)   equals the number of neutrons.
D)   changes after each reaction.
E)   depends on the number of electrons in the outermost shell.F) C) and D)
G) A) and E) A

Question 10

All carbohydrate molecules

Accepted Answer

A)   contain amino acids.
B)   contain nitrogen and phosphate.
C)   are organic acids.
D)   are composed of atoms of C, H, and the functional group -OH.
E)   are composed of atoms of C, H, O, and N.F) A) and C)
G) C) and D)

Question 11

Enzymes are organic compounds classified as

Accepted Answer

A)   nucleic acids.
B)   carbohydrates.
C)   lipids.
D)   steroids.
E)   proteins.F) B) and C)
G) B) and E)

Question 12

In the search to discover the agents that cause mad cow disease, scrapie in sheep, and CJD and kuru in humans, diseased brain tissues were passed through a fine filter to remove bacteria. The filtrate was still infectious, indicating that something smaller than bacteria must be the causative agent. If a virus was responsible for these brain diseases, then the infectious agent would contain either RNA or DNA. Other possibilities were that the agent was a carbohydrate, fat, or protein. Tissue filtrates were treated with agents that destroyed just one of these chemicals and then injected into a healthy animal, with the results as follows. What is the infectious agent? •Amylase digests carbohydrates; tissue filtrate still infects healthy test animal.
•Lipase digests fats; tissue filtrate still infects healthy test animal.
•Formaldehyde and/or heat denatures DNA and RNA; tissue filtrate still infects healthy test animal.
•Trypsin digests protein; tissue filtrate does not infect healthy test animal.

Accepted Answer

A)   carbohydrate
B)   fat
C)   protein
D)   DNA or RNA
E)   carbohydrate, fat, or DNA or RNA; but not proteinF) A) and E)
G) B) and D)

Question 13

Which of the following molecules is inorganic?

Accepted Answer

A)   CH4
B)   CO2
C)   C6H12O6
D)   C12H22O12
E)   C6H6F) A) and B)
G) All of the above

Question 14

Which of the following radioactive isotopes are used to detect whether or not an individual has a healthy thyroid?

Accepted Answer

A)   I131
B)   C14
C)   glucose
D)   H2
E)   All of the answer choices can be used.F) C) and E)
G) D) and E)

Question 15

Which of the following is a function of ATP within the cell?

Accepted Answer

A)   conduction of nerve impulses
B)   contraction of muscle cells
C)   synthesis of macromolecules
D)   energy currency of the cell
E)   All of the answer choices are functions of ATP within the cell.F) C) and D)
G) B) and D)

Question 16

Rain falling in the northeastern United States has a pH between 5.0 and 4.0. Normally, rainwater has a pH of about 5.6. Which of the following statements is correct?

Accepted Answer

A)   The pH of the rainwater has changed from neutral to acidic.
B)   The pH of the rainwater has become more acidic.
C)   The hydrogen ion (H+)  content of the rainwater has decreased.
D)   The proportion of hydroxide ions (OH-)  in the rainwater has increased.
E)   The rainwater with a pH of 4.0 is a thousand times more acidic than the rainwater with a pH of 5.0.F) B) and E)
G) A) and E)

Question 17

A covalent bond is

Accepted Answer

A)   a type of bond that results in ionic compounds.
B)   formed from the transfer of electrons from one atom to another.
C)   a sharing of electrons between two atoms.
D)   an attraction of charged atoms.
E)   a sharing of protons between two atoms.F) D) and E)
G) B) and C)

Question 18

Cholesterol is a component of cell membranes and is an example of which type of lipid?

Accepted Answer

A)   steroids
B)   phospholipids
C)   fatty acids
D)   triglycerides
E)   oilsF) B) and C)
G) A) and E)

Question 19

The final shape of a protein is very important to its function. When proteins undergo an irreversible change in shape called ________ they ________ perform their usual functions.

Accepted Answer

A)   naturation/can
B)   naturation/cannot
C)   denaturation/can
D)   denaturation/cannot
E)   dehydration reaction/cannotF) None of the above
G) A) and E) D

Question 20

Removal of the sulfhydryl functional group would disrupt the structure of

Accepted Answer

A)   sugars and some amino acids.
B)   sugars.
C)   fatty acids.
D)   proteins.
E)   nucleotides and fatty acids.F) A) and C)
G) A) and E)

Exam 2: The Molecules of Cells

Which of the following is a property of water that results from hydrogen bonding?

Correct Answer
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Organic molecules

Correct Answer
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Which statement about DNA and RNA is correct?

Correct Answer
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________ is a polysaccharide that is found in plant cell walls and accounts for their strength.

Correct Answer
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The lower the pH

Correct Answer
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What type of reaction is necessary to produce a dipeptide from individual amino acids?

Correct Answer
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Potassium hydroxide (KOH) almost completely dissociates in aqueous solution into K⁺ and OH^-, which means it is a(n)

Correct Answer
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Which type of bond formation is responsible for the properties of lipids?

Correct Answer
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D

The atomic mass of an element

Correct Answer
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A

All carbohydrate molecules

Correct Answer
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Enzymes are organic compounds classified as

Correct Answer
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Correct Answer
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Which of the following molecules is inorganic?

Correct Answer
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Which of the following radioactive isotopes are used to detect whether or not an individual has a healthy thyroid?

Correct Answer
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Which of the following is a function of ATP within the cell?

Correct Answer
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Rain falling in the northeastern United States has a pH between 5.0 and 4.0. Normally, rainwater has a pH of about 5.6. Which of the following statements is correct?

Correct Answer
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A covalent bond is

Correct Answer
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Cholesterol is a component of cell membranes and is an example of which type of lipid?

Correct Answer
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The final shape of a protein is very important to its function. When proteins undergo an irreversible change in shape called they perform their usual functions.

Correct Answer
verified
D

Removal of the sulfhydryl functional group would disrupt the structure of

Correct Answer
verified

Exam 2: The Molecules of Cells

Which of the following is a property of water that results from hydrogen bonding?

Correct AnswerverifiedShow Answer

Organic molecules

Correct AnswerverifiedShow Answer

Which statement about DNA and RNA is correct?

Correct AnswerverifiedShow Answer

________ is a polysaccharide that is found in plant cell walls and accounts for their strength.

Correct AnswerverifiedShow Answer

The lower the pH

Correct AnswerverifiedShow Answer

What type of reaction is necessary to produce a dipeptide from individual amino acids?

Correct AnswerverifiedShow Answer

Potassium hydroxide (KOH) almost completely dissociates in aqueous solution into K+ and OH-, which means it is a(n)

Correct AnswerverifiedShow Answer

Which type of bond formation is responsible for the properties of lipids?

Correct AnswerverifiedD

The atomic mass of an element

Correct AnswerverifiedA

All carbohydrate molecules

Correct AnswerverifiedShow Answer

Enzymes are organic compounds classified as

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Which of the following molecules is inorganic?

Correct AnswerverifiedShow Answer

Which of the following radioactive isotopes are used to detect whether or not an individual has a healthy thyroid?

Correct AnswerverifiedShow Answer

Which of the following is a function of ATP within the cell?

Correct AnswerverifiedShow Answer

Rain falling in the northeastern United States has a pH between 5.0 and 4.0. Normally, rainwater has a pH of about 5.6. Which of the following statements is correct?

Correct AnswerverifiedShow Answer

A covalent bond is

Correct AnswerverifiedShow Answer

Cholesterol is a component of cell membranes and is an example of which type of lipid?

Correct AnswerverifiedShow Answer

The final shape of a protein is very important to its function. When proteins undergo an irreversible change in shape called ________ they ________ perform their usual functions.

Correct AnswerverifiedD

Removal of the sulfhydryl functional group would disrupt the structure of

Correct AnswerverifiedShow Answer

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Potassium hydroxide (KOH) almost completely dissociates in aqueous solution into K⁺ and OH^-, which means it is a(n)

Correct Answer
verified

Correct Answer
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D

Correct Answer
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A

Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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Correct Answer
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The final shape of a protein is very important to its function. When proteins undergo an irreversible change in shape called they perform their usual functions.

Correct Answer
verified
D

Correct Answer
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