Question 1

The atomic weight of an element whose atoms contain 8 protons, 8 electrons, and 8 neutrons is

Accepted Answer

A)  8.
B)  16.
C)  24.
D)  32.E) A) and D)
F) B) and C)

Question 2

A base is an electrolyte that releases ions that combine with hydrogen ions.

Accepted Answer

A) True 
 B)False

Question 3

Lipids

Accepted Answer

A)  are insoluble in water.
B)  include phospholipids, cholesterol, and fats.
C)  contain C, H, and O, but with proportionately less oxygen than in carbohydrates.
D)  All of the answer choices are correct.E) None of the above
F) All of the above

Question 4

Chemically inert atoms always have their outermost electron shell full.

Accepted Answer

A) True 
 B)False

Question 5

A complete atom is electrically neutral because

Accepted Answer

A)  the number of protons equals the number of neutrons.
B)  the number of electrons equals the number of neutrons.
C)  the number of electrons equals the number of protons.
D)  the number of electrons is greater than the number of protons.E) A) and B)
F) A) and C)

Question 6

DNA

Accepted Answer

A)  is a protein.
B)  plays no role in the synthesis of fats.
C)  stores genetic information, including instructions for enzymes that synthesize fats and carbohydrates.
D)  is routinely broken down to provide cellular energy.E) None of the above
F) B) and C)

Question 7

In phenylketonuria, an individual cannot break down the amino acid phenylalanine. Molecules that include phenylalanine build up in the blood, which causes intellectual disability and other symptoms. This inherited disease can be controlled by following a diet that is very low in

Accepted Answer

A)  carbohydrates.
B)  cholesterol.
C)  protein.
D)  nucleic acids.E) A) and B)
F) A) and C)

Question 8

Nucleic acids are

Accepted Answer

A)  very small, simple molecules.
B)  structural molecules that have no function other than support.
C)  composed of building blocks called nucleotides.
D)  primary sources of cellular energy.E) All of the above
F) A) and D)

Question 9

Sodium ions and calcium ions are examples of

Accepted Answer

A)  cations.
B)  uncharged particles.
C)  anions.
D)  salts.E) None of the above
F) B) and D)

Question 10

A substance is added to a protein sample that does not alter the composition or amino acid sequence of the protein itself, but changes its three-dimensional structure. Which of the following was altered by the substance?

Accepted Answer

A)  Oxygen double bonds
B)  Covalent bonds
C)  Ionic bonds
D)  Hydrogen bondsE) A) and C)
F) C) and D)

Question 11

Isotopes of an element have

Accepted Answer

A)  the same atomic number and same atomic weight.
B)  the same atomic number but different atomic weights.
C)  different atomic numbers but the same atomic weight.
D)  different atomic numbers and different atomic weights.E) A) and B)
F) None of the above

Question 12

________ are building blocks of nucleic acids.

Accepted Answer

The answer of ________ are building blocks of nucleic acids....

Question 13

The pH scale measures the

Accepted Answer

A)  concentration of hydrogen ions in solution.
B)  number of molecules of salts dissolved in water.
C)  number of hydroxide ions in water.
D)  strength of an electrical current that a solution carries.E) A) and B)
F) B) and C)

Question 14

Which of the following is the most abundant inorganic substance in the body?

Accepted Answer

A)  Carbohydrate
B)  Water
C)  Lipid
D)  ProteinE) A) and D)
F) B) and C)

Question 15

Which of the following isotopes has the longest half-life?

Accepted Answer

A)  Iodine-131
B)  Iron-59
C)  Phosphorus-32
D)  Cobalt-60E) C) and D)
F) A) and B)

Question 16

Cholesterol, a type of lipid, is composed of three fatty acid chains attached to glycerol.

Accepted Answer

A) True 
 B)False

Question 17

Glycogen is stored in the liver and ________.

Accepted Answer

A)  spleen
B)  skeletal muscles
C)  pancreas
D)  heartE) B) and C)
F) A) and D)

Question 18

The atomic number of an atom equals the number of ________, and the atomic weight equals the ________.

Accepted Answer

A)  neutrons; number of protons
B)  protons; weight of all the electrons
C)  neutrons; number of protons plus electrons
D)  protons; number of protons plus neutronsE) A) and B)
F) A) and C)

Question 19

Which of the following groups of elements accounts for more than 95% of the human body by weight?

Accepted Answer

A)  Carbon, hydrogen, oxygen, nitrogen
B)  Calcium, hydrogen, oxygen, nitrogen
C)  Carbon, phosphorus, oxygen, hydrogen
D)  Calcium, phosphorus, hydrogen, nitrogenE) All of the above
F) None of the above

Question 20

Which of the following is not a source of ionizing radiation?

Accepted Answer

A)  Cosmic rays from outer space
B)  Cholesterol and triglycerides
C)  Atomic and nuclear weapons
D)  Smoke detectorsE) C) and D)
F) B) and D)

Exam 2: Chemical Basis of Life

Cholesterol, a type of lipid, is composed of three fatty acid chains attached to glycerol.

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In phenylketonuria, an individual cannot break down the amino acid phenylalanine. Molecules that include phenylalanine build up in the blood, which causes intellectual disability and other symptoms. This inherited disease can be controlled by following a diet that is very low in

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A base is an electrolyte that releases ions that combine with hydrogen ions.

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DNA

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Lipids

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Which of the following groups of elements accounts for more than 95% of the human body by weight?

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A complete atom is electrically neutral because

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Sodium ions and calcium ions are examples of

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________ are building blocks of nucleic acids.

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The atomic weight of an element whose atoms contain 8 protons, 8 electrons, and 8 neutrons is

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Nucleic acids are

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Which of the following isotopes has the longest half-life?

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A substance is added to a protein sample that does not alter the composition or amino acid sequence of the protein itself, but changes its three-dimensional structure. Which of the following was altered by the substance?

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Which of the following is the most abundant inorganic substance in the body?

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Chemically inert atoms always have their outermost electron shell full.

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The pH scale measures the

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Glycogen is stored in the liver and ________.

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The atomic number of an atom equals the number of ________, and the atomic weight equals the ________.

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Which of the following is not a source of ionizing radiation?

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Isotopes of an element have

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The atomic number of an atom equals the number of , and the atomic weight equals the .

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