Unit 2: The Chemistry of Life

Question 1

MATTER

Answer 1

anything that takes up space and has mass; the three usual forms of matter are solid, liquid, and gas

Question 2

ELEMENT

Answer 2

a chemical substance that contains only one kind of atom and that cannot be broken down into simpler substances

Question 3

ATOM

Answer 3

a tiny particle that is the fundamental building block of all substances and whose properties determine the properties of an element made up only of those atoms

Question 4

PROTONS

Answer 4

a positively charged particle found in the nuclei of atoms

Question 5

NEUTRONS

Answer 5

a neutral particle with approximately the same mass as a proton, found in nuclei of atoms along with protons

Question 6

ELECTRONS

Answer 6

a tiny part of an atom with a negative electrical charge

Question 7

ION

Answer 7

an atom that has a positive or negative electrical charge

Question 8

MOLECULES

Answer 8

any compound resulting from covalent bonding

Question 9

VALENCE ELECTRONS

Answer 9

the electrons in any atom´s outer orbital path

Question 10

IONIC BOND

Answer 10

the force of attraction between a charged atom (or group of connected atoms) and another with the opposite charge

Question 11

COVALENT BOND

Answer 11

a bond in which electrons are shared between the bonded atoms

Question 12

HYDROGEN BOND

Answer 12

the force of attraction between a partially charged atom and a hydrogen atom that is covalently bonded to another partially charged atom

Question 13

ENTROPY

Answer 13

the randomness of any physical system

Question 14

ORGANIC COMPOUNDS

Answer 14

any chemical compound that contains carbon bonded to at least one other atom, usually hydrogen

Question 15

MACROMOLECULE

Answer 15

a large molecule, especially applied to carbohydrates, proteins, lipids, and nucleic acids

Question 16

CARBOHYDRATES

Answer 16

one of the four major classes of large organic molecules made from carbon, oxygen, and hydrogen

Question 17

LIPID

Answer 17

fats, oils, phospholipids, steroids, and waxes; one of four major classes of large organic molecules

Question 18

PROTEINS

Answer 18

one of the four major classes of large organic molecules, made of amino acids

Question 19

AMINO ACIDS

Answer 19

the organic molecules that serve as the units from which proteins are made

Question 20

NUCLEIC ACIDS

Answer 20

one of the four major classes of large organic molecules, which are important in storing, transmitting, and making useful the information necessary for the processes of life

Question 21

ORGANIC COMPOUND

Answer 21

any chemical compound that contains carbon bonded to at least one other atom, usually hydrogen

Question 22

CHLOROPHYLL

Answer 22

a molecule in plants that plays a key role in photosynthesis

Question 23

HEMOGLOBIN

Answer 23

a large molecule that captures oxygen from the lungs and delivers it to the rest of the body

Question 24

ENZYMES

Answer 24

a catalyst for chemical reactions within living things, increasing the rate of the reaction without being changed itself

Question 25

BIOLUMINESCENCE

Answer 25

light produced by a living organism

Question 26

ION

Answer 26

an atom that has a positive or negative electrical charge

Question 27

INORGANIC COMPOUND

Answer 27

a compound not formed from carbon-hydrogen bonds; more generally, a compound not produced by a living thing

Question 28

POLAR MOLECULE

Answer 28

a molecule in which there are positive and negative areas

Question 29

HYDROGEN BONDS

Answer 29

the force of attraction between a partially charged atom and a hydrogen atom that is covalently bonded to another partially charged atom

Question 30

COHESION

Answer 30

an attraction between molecules of the same substance

Question 31

ADHESION

Answer 31

an attraction between the molecules of one substance and the molecules of another substance

Question 32

SURFACE TENSION

Answer 32

the force that holds molecules together on the surface of a liquid

Question 33

SOLVENT

Answer 33

a substance in which something is dissolved

Question 34

SOLUTE

Answer 34

a substance that dissolves in solvent