Chapter 2 - The Chemical Basis of Life

Question 1

the scientific discipline concerned with the atomic composition and structure of substances and the reactions they undergo.

Answer 1

Chemistry

Question 2

About _______ of the body’s weight results from the elements oxygen, carbon, hydrogen, and nitrogen.

Answer 2

96%

Question 3

do not have an electrical charge

Answer 3

neutrons

Question 4

have positive charges

Answer 4

protons

Question 5

have negative charges

Answer 5

electrons

Question 6

The nucleus accounts for 99.97% of an atom’s mass, but only 1-ten- a trillionth of its volume. True or False

Answer 6

True

Question 7

The chemical behavior of an atom is not dependent on its electrons. True or False

Answer 7

False (dependent)

Question 8

__________ is the ability of the atom’s nucleus to pull electrons toward it.

Answer 8

Electronegativity

Question 9

a charged particle

Answer 9

ion

Question 10

sharing of one pair of electrons by two atoms

Answer 10

single covalent bond

Question 11

two atoms share two pairs of electrons

Answer 11

double covalent bond

Question 12

an unequal, asymmetrical sharing of electrons

Answer 12

polar covalent bond

Question 13

Molecules with this asymmetrical electrical charge

Answer 13

polar molecules

Question 14

an equal sharing of electrons between atoms, it is because their electronegativities are the same

Answer 14

nonpolar covalent bond

Question 15

Molecules with a symmetrical electrical charge

Answer 15

nonpolar molecules

Question 16

The positive end of one polar molecule can be weakly attracted to the negative end of another polar molecule

Answer 16

hydrogen bond

Question 17

All compounds are molecules. True or False

Answer 17

False (Some compounds are molecules and some are not)

Question 18

dissociated ion

Answer 18

electrolytes

Question 19

The formation or breaking of chemical bonds between atoms, ions, molecules, or compounds

Answer 19

chemical reaction

Question 20

The substances that enter into a chemical reaction

Answer 20

reactants

Question 21

The substances that result from the chemical reaction

Answer 21

products

Question 22

When two or more reactants combine to form a larger, more complex product, the process is called a ______________

Answer 22

synthesis reaction

Question 23

All of the synthesis reactions that occur in the body are collectively referred to as _____

Answer 23

anabolism

Question 24

Synthesis reactions in which water is also a product are called __________

Answer 24

dehydration reactions

Question 25

reactants are broken down into smaller, less complex products

Answer 25

decomposition reaction

Question 26

The decomposition reactions that occur in the body

Answer 26

catabolism

Question 27

Reactions that use water

Answer 27

hydrolysis reactions

Question 28

All of the anabolic and catabolic reactions in the body

Answer 28

metabolism

Question 29

An __________ is a combination of a decomposition reaction and a synthesis reaction.

Answer 29

exchange reaction

Question 30

the reaction can run in the opposite direction so that the products are converted back to the original reactants.

Answer 30

reversible reaction

Question 31

the rate of product formation is equal to the rate of reactant formation

Answer 31

equilibrium

Question 32

stored energy

Answer 32

Potential energy

Question 33

caused by the movement of an object and is the form of energy that actually does work

Answer 33

Kinetic energy

Question 34

a form of potential energy stored in chemical bonds

Answer 34

chemical energy

Question 35

According to the law of conservation of energy, the total energy of the universe is inconsistent. True or False

Answer 35

False (constant)

Question 36

___________ is energy resulting from the position or movement of objects.

Answer 36

Mechanical energy

Question 37

If blood pH drops below 7.35, a condition called _______ results

Answer 37

acidosis

Question 38

If blood pH rises above 7.45, _________ results

Answer 38

alkalosis

Question 39

a chemical that resists changes in pH

Answer 39

buffer

Question 40

organic chemistry deals with those substances that do not contain carbon, whereas inorganic chemistry is the study of carbon-containing substances. True or False.

Answer 40

False (inorganic, organic)

Question 41

simplest carbohydrates

Answer 41

monosaccharides

Question 42

formed when two monosaccharides are joined by a covalent bond

Answer 42

disaccharides

Question 43

consist of many monosaccharides bound in long chains

Answer 43

polysaccharides

Question 44

a polysaccharide of glucose

Answer 44

glycogen

Question 45

substances that dissolve in nonpolar solvents, such as alcohol or acetone, but not in polar solvents, such as water.

Answer 45

lipids

Question 46

a protein catalyst that increases the rate at which a chemical reaction proceeds without the enzyme being permanently changed

Answer 46

enzyme