Deck 2: Chemistry of Life

Question 1

An element is any substance that contains one type of

A)molecule.
B)isotope.
C)atom.
D)proton.

Answer 1

C

Question 2

Exactly 6.02 x 10²³ atoms of any element is called one ____ of that element.

A)atomic mass unit
B)isotope
C)mole
D)mouse

Answer 2

C

Question 3

An atom or group of atoms with a charge is called a(n)

A)molecule.
B)isotope.
C)compound.
D)ion.

Answer 3

D

Question 4

Low levels of radiation are commonly used to

A)sterilize dental products.
B)destroy cancer cells.
C)produce images of body parts.
D)All apply.

Question 5

Atoms with more than one shell are most stable when the outermost shell contains _____ electrons.

A)10
B)1
C)8
D)6

Question 6

Which subatomic particle determines the chemical activity of an atom?

A)Neutron
B)Proton
C)Electron
D)Prion

Question 7

The positively charged particles in the nucleus of an atom are

A)neutrons.
B)electrons.
C)protons.
D)isotopes.

Question 8

The smallest unit of matter is the

A)molecule.
B)atom.
C)compound.
D)isotope.

Question 9

The atomic mass of a proton is

A)0 atomic mass units.
B)2 atomic mass units.
C)1 atomic mass units.
D)-1 atomic mass units.

Question 10

If the atomic number of an element is 9 and the mass number is 19,how many neutrons does the atom have?

A)10
B)9
C)19
D)28

Question 11

Which is characteristic of an ion?

A)Contains an unequal number of electrons and protons
B)Contains a different number of neutrons
C)Contains extra protons
D)Contains equal numbers of protons,electrons,and neutrons

Question 12

Compared to "regular" isotopes,radioactive isotopes

A)emit energy from the nucleus.
B)lose or gain neutrons.
C)lose or gain electrons.

Question 13

What makes an isotope radioactive?

A)It has more protons than electrons.
B)It releases energy to become stable.
C)It releases hydrogen ions into solution.
D)It breaks down into hydrogen and electrons.

Question 14

Which of the following subatomic particles are found in the nucleus of an atom?

A)Protons and electrons
B)Electrons and neutrons
C)Protons and shells
D)Neutrons and protons

Question 15

Which subatomic particle determines the identity of an atom?

A)Neutron
B)Proton
C)Electron
D)Prion

Question 16

The number of an element is equal to

A)protons plus the number of neutrons.
B)protons plus the number of electrons.
C)protons.
D)electrons plus the number of neutrons.

Question 17

The number of protons in an atom is called the

A)atomic number.
B)atomic weight.
C)mass number.
D)combining weight.

Question 18

Over 90% of the body is composed of four elements: carbon,nitrogen,chlorine,and hydrogen.

Question 19

Different forms of the same element with different numbers of neutrons are called

A)molecules.
B)compounds.
C)isotopes.
D)lattices.

Question 20

If the atomic number of an element is 27 and the mass number is 60,how many neutrons does the atom have?

A)27
B)33
C)87
D)60

Question 21

Water molecules are

A)polar.
B)nonpolar.

Question 22

When two pairs of electrons are shared between two atoms,a ______ bond is formed.

A)single covalent
B)double covalent
C)triple covalent
D)double ionic

Question 23

Molecules form from

A)the shape of the individual atoms.
B)the attraction between electrons.
C)the sharing of electrons.
D)a drive toward solubility.

Question 24

The attraction between a slightly positive hydrogen to a slightly negative oxygen of another molecule describes a(n)________ bond.

A)hydrogen
B)oxygen
C)nitrogen
D)ionic

Question 25

A bond created from the sharing of electrons between two atoms is a(n)______ bond.

A)covalent
B)hydrogen
C)ionic
D)metallic

Question 26

When one atom has a stronger attraction for shared electrons than the other atom,a(n)___________ covalent bond is formed.

A)polar
B)nonpolar
C)ionic
D)metallic

Question 27

Which of the following is NOT a property of water?

A)High heat capacity
B)Low heat of vaporization
C)Solvent for polar and ionic compounds
D)Cohesiveness

Question 28

Substances that dissolve in water are called

A)hydrophilic.
B)hydrophobic.
C)hydrophoric.
D)hydrochromic.

Question 29

An anion is an atom or molecule that

A)is positively charged.
B)is negatively charged.
C)emits radioactive energy.

Question 30

High levels of radiation are NOT used

A)to sterilize medical equipment.
B)to kill cancer cells.
C)as tracers to detect molecular changes.
D)to sterilize medical tools and equipment.

Question 31

A bond created from the attraction between positively and negatively charged ions is a(n)______ bond.

A)covalent
B)hydrogen
C)ionic
D)metallic

Question 32

Atoms bonded together to form a chemical unit are called

A)molecules.
B)ions.
C)radioisotopes.
D)buffers.

Question 33

The ability of water molecules to cling to each other is _________,while the ability to cling to other surfaces is ___________.

A)cohesion;adhesion
B)dissolving;vaporization
C)adhesion;cohesion
D)cohesion;dissolving

Question 34

The most abundant molecule in living organisms is

A)water.
B)glucose.
C)oxygen.
D)ammonia.

Question 35

Organic compounds always contain ___________ atoms.

A)water
B)carbon
C)nitrogen
D)oxygen

Question 36

Which of the following is NOT a property of water?

A)The ability to cling to other water molecules,yet flow
B)The ability to facilitate chemical reactions
C)The ability to insulate the body from temperature extremes
D)The ability to dissolve nonpolar,hydrophobic molecules

Question 37

Equal sharing of electrons is a characteristic of a _______ covalent bond,while unequal sharing is in a _______ bond.

A)polar;nonpolar
B)nonpolar;polar

Question 38

Ionic bonds involve _______,while covalent bonds involve _______.

A)the donation of electrons;the sharing of electrons
B)the sharing of electrons;the donation of electrons
C)weak attractions;the donation of electrons

Question 39

Sodium chloride dissociates when dissolved in water.Therefore,it is considered a ______.

A)salt
B)compound
C)acid
D)base

Question 40

A molecule made of two or more different atoms bonded together is called a(n)

A)ion.
B)isotope.
C)atom.
D)compound.

Question 41

A pH of 5.5 would be considered

A)acidic.
B)basic.
C)neutral.

Question 42

An electrolyte is a substance that releases _____ when dissolved in water.

A)ions
B)electrons
C)bases

Question 43

Chemicals that help keep body fluids within a normal pH range are called

A)acids.
B)bases.
C)buffers.
D)salts.

Question 44

A substance that can take up hydrogen ions or release hydroxide ions in water is a(n)

A)salt.
B)base.
C)protein.
D)acid.

Question 45

The monomer of carbohydrates is a

A)nucleotide.
B)fatty acid.
C)monosaccharide.
D)amino acid.

Question 46

The lower the pH,

A)the lesser the hydrogen ion concentration.
B)the more acidic the solution.
C)the lesser the hydrogen ion concentration and the more acidic the solution.
D)the greater the hydroxide ion concentration.
E)the more basic the solution and the greater the hydroxide ion concentration.

Question 47

The removal of a water molecule during a reaction results in

A)breaking a bond.
B)forming an acid.
C)hydrolysis.
D)forming a bond.

Question 48

A pH of 7.0 would be considered

A)acidic.
B)basic.
C)neutral.

Question 49

The ability of water to absorb large amounts of heat energy without changing its temperature is a

A)low specific heat capacity.
B)low heat of vaporization.
C)high specific heat capacity.
D)high heat of vaporization.

Question 50

A substance that dissociates in water,releasing hydrogen ions,is a(n)

A)salt.
B)base.
C)protein.
D)acid.

Question 51

What monomer is NOT correctly matched with its macromolecule?

A)carbohydrates - glucose
B)lipids - glycerol and citric acids
C)proteins - amino acids
D)nucleic acids - nucleotides

Question 52

Which arrow in the following equation represents dehydration?

A)Arrow 1
B)Arrow 2

Question 53

The main function of carbohydrates is to provide

A)cellular energy.
B)insulation.
C)transport molecules.
D)hereditary information.

Question 54

A weak base will accept many hydrogen ions,while a strong base will accept only a few hydrogen ions.

Question 55

A monosaccharide of five carbons is a

A)hexose sugar.
B)glycerol.
C)fatty acid.
D)pentose sugar.

Question 56

The subunit molecules for proteins are

A)nucleic acids.
B)amino acids.
C)fatty acids.
D)monosaccharides.

Question 57

A blood pH of 7.2 would be considered _______,while a pH of 7.6 would be _______.

A)acidosis;alkalosis
B)alkalosis;acidosis
C)acidosis;normal
D)Both values are within the normal range.

Question 58

The pH of the blood is slightly basic.Which of the following describes this pH?

A)6.4
B)12.6
C)4.7
D)7.4

Question 59

Hydrochloric acid is considered a strong acid because it

A)produces very few hydrogen ions in water.
B)produces many hydroxide ions in water.
C)produces many hydrogen ions in water.
D)dissociates very little in water.

Question 60

The addition of water in an enzyme-catalyzed reaction is a(n)________ reaction.

A)dehydration
B)hydrolysis
C)exchange
D)neutralization

Question 61

Which of the following is the main component of fiber in our diet?

A)Glycogen
B)Protein
C)Cellulose
D)Starch

Question 62

The coiling and folding of a polypeptide chain into a more circular molecule is the ______ structure of a protein.

A)primary
B)secondary
C)tertiary
D)quaternary

Question 63

Which of the following is NOT a function of proteins?

A)They form structural components such as collagen.
B)They form many hormones.
C)They form actin and myosin needed for muscular movement.
D)They form important energy molecules.

Question 64

Which of the following is NOT a function of proteins?

A)They form enzymes to speed up reactions.
B)They form the backbone of cell membranes.
C)They form hemoglobin to transport oxygen in the blood.
D)They form antibodies to protect the body from disease.

Question 65

How many different amino acids compose all human polypeptides (proteins)?

A)10
B)15
C)20
D)25

Question 66

Which of the following is NOT a function of lipids?

A)Long-term energy storage
B)Formation of antibodies
C)Formation of cell membranes
D)Component of sex hormones

Question 67

Which of the following is NOT a disaccharide?

A)Maltose
B)Galactose
C)Lactose
D)Sucrose

Question 68

Which of the following is NOT a monosaccharide?

A)Glucose
B)Fructose
C)Sucrose
D)Galactose

Question 69

When fatty acids contain one or more double bonds,they are considered

A)saturated.
B)unsaturated.
C)emulsified.
D)synthesized.

Question 70

Organic compounds that are always insoluble in water are called

A)sugars.
B)lipids.
C)nucleotides.
D)proteins.

Question 71

Fats are usually liquid at room temperature and oils are solids.

Question 72

The coiling or folding of a polypeptide chain is the ________ structure of a protein.

A)primary
B)secondary
C)tertiary
D)quaternary

Question 73

Steroids differ in structure from other lipids in that they have a backbone of

A)four fused carbon rings.
B)branched chains of carbons.
C)saturated carbon chains.
D)unsaturated carbon chains.

Question 74

Which of the following contains glucose?

A)Protein
B)Fat
C)Nucleic acid
D)Starch

Question 75

The macromolecules that are the main component of cell membranes are

A)steroids.
B)triglycerides.
C)phospholipids.
D)prostaglandins.

Question 76

The process that allows fats to mix with water,particularly so digestion can occur,is called

A)hydrolysis.
B)degradation.
C)dehydration.
D)emulsification.

Question 77

Which macromolecule is composed of one glycerol plus three fatty acids?

A)Lipids
B)Proteins
C)Nucleic acids
D)Carbohydrates

Question 78

What makes a phospholipid different from a fat?

A)Fats are neutral while phospholipids are ionized.
B)Fats are solid while phospholiopids are liquid.
C)Fats are ionized while phospholipids are neutral.
D)Fats are basic while phospholipids are acidic.

Question 79

The sequence of amino acids makes up the ______ structure of a protein.

A)primary
B)secondary
C)tertiary
D)quaternary

Question 80

Glycogen is

A)a monosaccharide used for quick energy.
B)a protein found in cell membranes.
C)a polysaccharide used as stored energy in animals.
D)a fat found in margarine.