Chapter 2 - Chemistry Of Life

Question 1

acid

Answer 1

A substance that donates hydrogen ions and therefore lowers pH.

Question 2

adhesion

Answer 2

The attraction between water molecules and molecules of a different substance.

Question 3

amino acid

Answer 3

A monomer of protein.

Question 4

anion

Answer 4

A negative ion formed by gaining an electron.

Question 5

atomic number

Answer 5

The number of protons in an atom.

Question 6

base

Answer 6

A substance that absorbs hydrogen ions and therefore raises pH.

Question 7

buffer

Answer 7

A solution that resists a change in pH by absorbing or releasing hydrogen or hydroxide ions

Question 8

carbohydrate

Answer 8

A biological macromolecule in which the ratio of carbon to hydrogen to oxygen is 1:2:1; carbohydrates serve as energy sources and structural support in cells.

Question 9

cation

Answer 9

A positive ion formed by losing electrons.

Question 10

cellulose

Answer 10

A polysaccharide that makes up the cell walls of plants and provides structural support to the cell.

Question 11

chemical bond

Answer 11

An interaction between two or more of the same or different elements that results in the formation of molecules.

Question 12

chitin

Answer 12

A type of carbohydrate that forms the outer skeleton of arthropods, such as insects and crustaceans, and the cell walls of fungi

Question 13

cohesion

Answer 13

The intermolecular forces between water molecules caused by the polar nature of water; creates surface tension

Question 14

covalent bond

Answer 14

A type of strong bond between two or more of the same or different elements; forms when electrons are SHARED between elements.

Question 15

denaturation

Answer 15

The loss of shape in a protein as a result of changes in temperature, pH, or exposure to chemicals.

Question 16

deoxyribonucleic acid

DNA

Answer 16

A double-stranded polymer of nucleotides that carries the hereditary information of the cell.

Question 17

disaccharide

Answer 17

Two sugar monomers that are linked together by a peptide bond.

Question 18

electron

Answer 18

A negatively charged particle that resides outside the nucleus in the electron orbital; lacks functional mass. Charge: -1

Question 19

electron transfer

Answer 19

The movement of electrons from one element to another.

Question 20

element

Answer 20

One of 118 unique substances that cannot be broken down into smaller substances and retain the characteristic of that substance; each element has a specified number of protons and unique properties.

Question 21

enzyme

Answer 21

A catalyst in a biochemical reaction that is usually a complex or conjugated protein.

Question 22

evaporation

Answer 22

The release of water molecules from liquid water to form water vapor.

Question 23

fat

Answer 23

A lipid molecule composed of 3 fatty acids and a glycerol (triglyceride) that typically exists in a solid form at room temperature.

Question 24

glycogen

Answer 24

A storage carbohydrate in animals.

Question 25

hormone

Answer 25

A chemical-signaling molecule, usually a protein or steroid, secreted by an endocrine gland or group of endocrine cells; acts to control or regulate specific physiological processes.

Question 26

hydrogen bond

Answer 26

A WEAK bond partially positively charged hydrogen atoms and partially negatively charged elements or molecules.

Question 27

hydrophilic

Answer 27

Describes a substance that dissolves in water; water-loving.

Question 28

hydrophobic

Answer 28

Describes a substance that does not dissolve in water; water-fearing.

Question 29

ion

Answer 29

An atom or compound that does not contain equal numbers of protons and electrons, and therefore has a net charge.

Question 30

ionic bond

Answer 30

A chemical bond that forms between ions of opposite charges.

Question 31

isotope

Answer 31

One or more forms of an element that have different numbers of neutrons.

Question 32

lipids

Answer 32

A class of macromolecules that are nonpolar and insoluble in water.

Question 33

litmus paper

Answer 33

Filter paper that has been treated with a natural water-soluble dye so it can be used as a pH indicator.

Question 34

macromolecule

Answer 34

A large molecule, often formed by polymerization of smaller monomers.

Question 35

mass number

Answer 35

Protons + Neutrons

Question 36

matter

Answer 36

Anything that has a mass and occupies space

Question 37

monosaccharide

Answer 37

A single unit or monomer of carbohydrates

Question 38

neutron

Answer 38

A particle with no charge, resides in nucleus. Mass =1

Question 39

nonpolar covalent bond

Answer 39

Electrons are SHARED EQUALLY between atoms, resulting in no regions with partial charges as in polar covalent bonds.

Question 40

nucleic acid

Answer 40

A biological macromolecule that carries the genetic information of a cell and carries instructions for the functioning of the cell.

Question 41

nucleotide

Answer 41

A monomer of nucleic acids, contains pentose sugar, a phosphate group, and a nitrogenous base

Question 42

nucleus

Answer 42

the dense center of an atom made up of protons and (except in hydrogen) neutrons.

Question 43

octet rule

Answer 43

Outermost she'll of an element with a low atomic number can hold 8 electrons.

Question 44

oil

Answer 44

An unsaturated fat that is a liquid at room temperature.

Question 45

periodic table of elements

Answer 45

An organizational chart of elements, indicating the atomic number and the mass number of each element; provides key information about the properties of the elements.

Question 46

pH scale

Answer 46

Scale ranging from 0 to 14 that measures the approximate concentration of hydrogen ions of a substance.

Question 47

phosphilipid

Answer 47

Major constituent of the membranes of cells; composed of two fatty acids and a phosphate group attached to a glycerol backbone.

Question 48

polar covalent bond

Answer 48

A type of covalent bond in which electrons are pulled toward one atom and away from another, resulting in slightly positive and slightly negative charged regions of the molecule.

Question 49

polypeptide

Answer 49

A long chain of amino acids linked by peptide bonds.

Question 50

polysaccharide

Answer 50

A long chain of monosaccharides. May be branched of unbranched.

Question 51

protein

Answer 51

A biological macromolecule composed of one or more chains of amino acids.

Question 52

proton

Answer 52

A positively charged particle that resides in the nucleus. | Mass=1 Charge=+1

Question 53

radioactive isotope

Answer 53

An isotope that spontaneously emits particles or energy to form a more stable element.

Question 54

ribonucleic acid | RNA

Answer 54

A single-stranded polymer of nucleotides that is involved in proteins synthesis.

Question 55

saturated fatty acid

Answer 55

A long-chain hydrocarbon with single covalent bonds in the carbon chain; the number of hydrogen atoms attached to the carbon skeleton is maximized.

Question 56

solvent

Answer 56

A substance capable of dissolving another substance.

Question 57

starch

Answer 57

A storage carbohydrate in plants.

Question 58

steroid

Answer 58

A type of lipid composed of four fused hydrocarbon rings.

Question 59

surface tension

Answer 59

Th cohesive force at the surface of a body of liquid that prevents the molecules from separating.

Question 60

temperature

Answer 60

Measure of molecular motion.

Question 61

trans-fat

Answer 61

A form of unsaturated fat with the hydrogen atoms neighboring the double bond across from each other rather than on the same side of the double bond

Question 62

triglyceride

Answer 62

A fat molecule; consists of 3 fatty acids linked to a glycerol molecule.

Question 63

unsaturated fatty acids

Answer 63

A long-chain hydrocarbon that has one or more than one double bonds in the hydrocarbon chain.

Question 64

van der Waals interaction

Answer 64

A weak attraction or interaction between molecules caused by slightly positively charged or slightly negatively charged atoms.