Chapter 2

Question 1

Solutions with a pH value less than 7 are known as _________ in nature.

Answer 1

Acidic

Question 2

Solutions are said to be _________ when the pH value is greater than 7.

Answer 2

basic

Question 3

PH Basic

Answer 3

Above 7

Question 4

Solutions are _________ when the pH value is 7.

Answer 4

neutral

Question 5

The smallest particle of an element that maintains the chemical properties of the element.

Answer 5

Atom

Question 6

An electrically charged atom; has unequal numbers of electrons and protons.

Answer 6

Ion

Question 7

A chemical particle composed of two or more atoms united by a covalent chemical bond.

Answer 7

molecule

Question 8

The study of the composition, structure, and reactions of matter.

Answer 8

chemistry

Question 9

The power to cause something to move; to work.

Answer 9

energy

Question 10

Anything that occupies space and has mass.

Answer 10

matter

Question 11

The simplest type of matter composed of atoms of only one kind that maintains unique chemical properties.

Answer 11

element

Question 12

Substance that releases protons; proton donor.

Answer 12

Acid

Question 13

Substance that accepts protons; proton acceptor.

Answer 13

base

Question 14

A shorthand system to track hydrogen ion concentration is substances; categorizes the acidity levels of substances.

Answer 14

PH scale

Question 15

A simple sugar organic substance with a 2:1 ratio of hydrogen to oxygen.

Answer 15

carbohydrate

Question 16

An organic substance composed of carbon, oxygen, and hydrogen.

Answer 16

lipid

Question 17

An atom has an atomic number of 19 and a mass number of 39. This atom will have

Select one:
a. 19 neutrons.
b. 20 neutrons.
c. 39 neutrons.
d. 58 neutrons.
e. 20 electrons.

Answer 17

b. 20 neutrons.

Question 18

The molecular formula H2O means

Select one:
a. 1 hydrogen atom and 2 oxygen atoms.
b. 1 hydrogen atom and 1 oxygen atom.
c. 2 hydrogen atoms and 1 oxygen atom.
d. 2 hydrogen atoms and 2 oxygen atoms.
e. None of these choices is correct.

Answer 18

c. 2 hydrogen atoms and 1 oxygen atom.

Question 19

Hydrogen bonds are important for all of the following except:

Select one:
a. producing surface tension in water
b. helping hold a protein structure together
c. helping hold DNA strands together
d. helping atoms give up or receive electrons

Answer 19

d. helping atoms give up or receive electrons

Question 20

The three forms of matter are:

Select one:
a. air, water, and solids.
b. solids, liquids, and gases.
c. blood, bone, and air.
d. vapor, water, and solid.

Answer 20

b. solids, liquids, and gases.

Question 21

Kinetic energy is

Select one:
a. the form of energy that actually does work.
b. movement of ions or electrons.
c. energy that flows between objects with different temperatures.
d. stored energy that could do work but is not doing so.
e. energy that moves in waves.

Answer 21

a. the form of energy that actually does work.

Question 22

Which of the following pairs is mismatched?

Select one:
a. synthesis reaction - two reactants combine to form a larger product
b. decomposition reaction - large reactant broken into smaller products
c. oxidation - gain of electrons
d. dehydration reaction - water is a product of the reaction
e. hydrolysis - water is used in decomposition reaction

Answer 22

c. oxidation - gain of electrons

Question 23

Molecules that form when electrons are shared unequally between atoms are called

Select one:
a. salt molecules.
b. polar molecules.
c. nonpolar molecules.
d. lopsided molecules.
e. None of these choices are correct.

Answer 23

b. polar molecules.

Question 24

Sucrose is formed when the simple sugars fructose and glucose are covalently bonded. This reaction releases water. What type of reaction is this?

Select one:
a. catabolic
b. hydrolysis
c. dehydration
d. monomeric

Answer 24

c. dehydration

Question 25

A neutral atom will become a cation if it Select one: a. gains electrons. b. gains protons. c. loses electrons. d. loses protons. e. gains neutrons.

Answer 25

c. loses electrons.

Question 26

Chemical substances that dissolve in water or react with water to release ions are known as Select one: a. buffers. b. enzymes. c. bases. d. inorganic compounds. e. electrolytes.

Answer 26

e. electrolytes.

Question 27

Why are cyanide compounds lethal to humans? Select one: a. They interfere with protein synthesis. b. They interfere with nerve impulses. c. They interfere with the production of ATP. d. They interfere with muscle contraction. e. All of these occur with cyanide poisoning.

Answer 27

c. They interfere with the production of ATP.

Question 28

Normal pH for blood is 7.35 to 7.45. Maintenance of the pH in this range is Select one: a. critical because enzymes work best within narrow ranges of pH. b. not critical because extreme pH values do not affect enzyme function. c. called denaturation. d. not required. e. None of these choices is correct.

Answer 28

a. critical because enzymes work best within narrow ranges of pH.

Question 29

Proteins Select one: a. are the body's source of immediate energy. b. are the building blocks of nucleotides. c. provide much of the structure of body cells and tissues. d. contain the genetic information of the cell. e. insulate and cushion the body.

Answer 29

c. provide much of the structure of body cells and tissues.

Question 30

A

Answer 30

Salt crystal

Question 31

B

Answer 31

Sodium Ion

Question 32

C

Answer 32

Chloride Ion

Question 33

D

Answer 33

Water Ions

Question 34

A

Answer 34

Polar (hydrophilic) region (phosphate containing region)

Question 35

B

Answer 35

Nonpolar (hydrophobic) region (fatty acids)

Question 36

C

Answer 36

Nitrogren

Question 37

D

Answer 37

Phosphorous

Question 38

E

Answer 38

Oxygen

Question 39

DNA Select one: a. must travel to ribosomes to function. b. contains the sugar deoxyribose. c. is a single-stranded molecule. d. is one of several amino acids. e. assembles amino acids to make proteins..

Answer 39

b. contains the sugar deoxyribose.

Question 40

Which of the following is determined by sequence of amino acids bound by peptide bonds? Select one: a. amino acid b. peptide bond c. primary structure of protein d. secondary structure of protein e. denaturation

Answer 40

c. primary structure of protein

Question 41

Phospholipids have a hydrophilic end which is Select one: a. polar and water-insoluble. b. polar and water-soluble. c. nonpolar and water -insoluble. d. nonpolar and water-soluble.

Answer 41

b. polar and water-soluble.

Question 42

A

Answer 42

water molecule

Question 43

B

Answer 43

hydrogen bond

Question 44

C

Answer 44

hydrogen atom

Question 45

D

Answer 45

oxygen atom

Question 46

E

Answer 46

hydrogen bond

Question 47

The smallest particle of an element that still has the chemical characteristics of that element is a(n) electron. molecule. neutron. proton. atom.

Answer 47

atom

Question 48

12C and 14C are atoms of different elements. isotopes. atoms with different atomic numbers. atoms with different numbers of protons. compounds.

Answer 48

isotopes.

Question 49

A cation is a(n) uncharged atom. positively charged atom. negatively charged atom. atom that has gained an electron.

Answer 49

positively charged atom.

Question 50

A polar covalent bond between two atoms occurs when one atom attracts shared electrons more strongly than another atom. atoms attract electrons equally. an electron from one atom is completely transferred to another atom. the molecule becomes ionized. a hydrogen atom is shared between two different atoms.

Answer 50

one atom attracts shared electrons more strongly than another atom.

Question 51

Table salt (NaCl) is an atom. organic. a molecule. a compound. a cation.

Answer 51

a compound.

Question 52

The weak attractive force between two water molecules forms a(n) covalent bond. hydrogen bond. ionic bond. compound. isotope.

Answer 52

hydrogen bond.

Question 53

Electrolytes are nonpolar molecules. covalent compounds. substances that usually don’t dissolve in water. found in solutions that do not conduct electricity. cations and anions that dissociate in water.

Answer 53

cations and anions that dissociate in water.

Question 54

In a decomposition reaction, anabolism occurs. proteins are formed from amino acids. large molecules are broken down to form small molecules. a dehydration reaction may occur. All of these are correct.

Answer 54

large molecules are broken down to form small molecules.

Question 55

Oxidation-reduction reactions can be synthesis or decomposition reactions. have one reactant gaining electrons. have one reactant losing electrons. can create ionic or covalent bonds. All of these are correct.

Answer 55

All of these are correct.

Question 56

Potential energy is energy caused by movement of an object. is the form of energy that is actually doing work. includes energy within chemical bonds. can never be converted to kinetic energy. All of these are correct.

Answer 56

includes energy within chemical bonds.

Question 57

Which of these descriptions of heat energy is not correct? Heat energy flows between objects that are at different temperatures. Heat energy can be produced from all other forms of energy. Heat energy can be released during chemical reactions. Heat energy must be added to break apart ATP molecules. Heat energy is always transferred from a hotter object to a cooler object.

Answer 57

Heat energy must be added to break apart ATP molecules.

Question 58

Which of these statements concerning enzymes is correct? Enzymes increase the rate of reactions but are permanently changed as a result. Enzymes are proteins that function as catalysts. Enzymes increase the activation energy requirement for a reaction to occur. Enzymes usually can only double the rate of a chemical reaction. Enzymes increase the kinetic energy of the reactants.

Answer 58

Enzymes are proteins that function as catalysts.

Question 59

Water is composed of two oxygen atoms and one hydrogen atom. has a low specific heat. is composed of polar molecules into which ionic substances dissociate. is produced in a hydrolysis reaction. is a very small organic molecule.

Answer 59

is composed of polar molecules into which ionic substances dissociate.

Question 60

When sugar is dissolved in water, the water is called the solute. solution. solvent.

Answer 60

solvent.

Question 61

Which of these is an example of a suspension? sweat water and proteins inside cells sugar dissolved in water red blood cells in plasma

Answer 61

red blood cells in plasma

Question 62

A solution with a pH of 5 is _____   and contains _______   H+ than (as) a neutral solution. a base, more a base, fewer an acid, more an acid, fewer neutral, the same number of

Answer 62

an acid, more

Question 63

A buffer slows down chemical reactions. speeds up chemical reactions. increases the pH of a solution. maintains a relatively constant pH. works by forming salts.

Answer 63

maintains a relatively constant pH.

Question 64

A conjugate acid-base pair acts as a buffer. can combine with H+ in a solution. can release H+ to combine with OH−. describes carbonic acid (H2CO3) and bicarbonate ions (HCO3−). All of these are correct.

Answer 64

All of these are correct.

Question 65

The polysaccharide used for energy storage in the human body is cellulose. glycogen. lactose. sucrose. starch.

Answer 65

glycogen.

Question 66

The basic units or building blocks of triglycerides are simple sugars (monosaccharides). double sugars (disaccharides). amino acids. glycerol and fatty acids. nucleotides.

Answer 66

glycerol and fatty acids.

Question 67

A  ______ fatty acid has one double covalent bond between carbon atoms. cholesterol monounsaturated phospholipid polyunsaturated saturated

Answer 67

monounsaturated

Question 68

The  _______ structure of a protein results from the folding of the pleated sheets or helices. primary secondary tertiary quaternary

Answer 68

tertiary

Question 69

According to the lock-and-key model of enzyme action, reactants must first be heated. enzyme shape is not important. each enzyme can catalyze many types of reactions. reactants must bind to an active site on the enzyme. enzymes control only a small number of reactions in the cell.

Answer 69

reactants must bind to an active site on the enzyme.

Question 70

DNA molecules contain genes. contain a single strand of nucleotides. contain the nucleotide uracil. are of three different types that have roles in protein synthesis. contain up to 100 nitrogenous bases.

Answer 70

contain genes.

Question 71

ATP is formed by the addition of a phosphate group to ADP. is formed with energy released during catabolic reactions. provides the energy for anabolic reactions. contains three phosphate groups. All of these are correct.

Answer 71

All of these are correct.

Question 72

primary structure of protein

Answer 72

sequence and shape = function

Question 73

secondary structure

Answer 73

fold and bending caused by pleat or helix

Question 74

tertiary structure

Answer 74

large scale folding, shape of folded sequence

Question 75

quaternary structure of protein

Answer 75

2+ proteins form functional unit