[Biology] Chapter 2 - Key Terms

Front 1

acid

Back 1

Any dissolved substance that donates H+ to other solutes or to water molecules.

Hint 1

p. 28

Front 2

atom

Back 2

Fundamental form of matter that has mass and takes up space, and cannot be broken apart by everyday means.

Hint 2

p. 18

Front 3

atomic number

Back 3

The number of protons in the nucleus of an atom: identifies an element.

Hint 3

p. 20

Front 4

base

Back 4

Any substance that accepts hydrogen ions (H+) when dissolved in water, thus forming hydroxyl ions (OH-). Also, the nitrogencontaining component of a nucleic acid.

Hint 4

p. 28

Front 5

chemical bond

Back 5

A union between the electron structures of two ore more atoms or inons.

Hint 5

p. 22

Front 6

cohesion

Back 6

blah

Hint 6

p. 27

Front 7

compound

Back 7

blah

Hint 7

p. 23

Front 8

covalent bond

Back 8

Sharing of one or more electrons between two atoms.

Hint 8

p. 24

Front 9

electric gradient

Back 9

A difference in electric charge between adjoining regions.

Hint 9

p. ?

Front 10

electron

Back 10

Negatively charged unit of matter, with particle-like and wavelike properties; occupies an orbital around atomic nucleus.

Hint 10

p. 20

Front 11

element

Back 11

Material consisting of atoms all with the same atomic number.

Hint 11

p. 18

Front 12

evaporation

Back 12

blah

Hint 12

p. 27

Front 13

hydrogen bond

Back 13

An intermolecular interaction between a covalently bonded hydrogen atom and a different atom bearing a negative charge (e.g., oxygen, fluorine, or nitrogen).

Hint 13

p. 25

Front 14

hydrophilic substance

Back 14

blah

Hint 14

p. 26

Front 15

hydrophobic substance

Back 15

blah

Hint 15

p. 26

Front 16

internal environment

Back 16

In animals, blood and interstitial fluid (extracellular fluid).

Hint 16

p. ?

Front 17

ion

Back 17

blah

Hint 17

p. 24

Front 18

ionic bond

Back 18

Interaction between ions held together by attraction of opposite charges.

Hint 18

p. 24

Front 19

isotopes

Back 19

Two or more forms of an element's atoms differing in the number of neutrons.

Hint 19

p. ?

Front 20

kilocalorie

Back 20

A thousand calories of heat energy, the amount needed to raise the temperature of 1 kilogram of water by 1 degree C. Standard unit of measure for the energy content of foods.

Hint 20

p. ?

Front 21

mass number

Back 21

The sum of all protons and neutrons in an atom's nucleus.

Hint 21

p. 20

Front 22

mixture

Back 22

Two or more elements intermingled in proportions that can and usually do vary.

Hint 22

p. 23

Front 23

molecule

Back 23

Two or more atoms of the same or different elements joined by chemical bonds.

Hint 23

p. 23

Front 24

neutron

Back 24

Subatomic particle found in an atom's nucleus; has mass but no charge.

Hint 24

p. 20

Front 25

nucleus

Back 25

Organelle that physically separates DNA from the cytoplasm in a eukaryotic cell.

Hint 25

p. ?

Front 26

periodic table

Back 26

Tabular arrangement of elements based on their chemical properties.

Hint 26

p. 20

Front 27

pH scale

Back 27

A measure of the H+ concentration (acidity) of blood, water, and other solutions. pH 7 is neutral.

Hint 27

p. 28

Front 28

proton

Back 28

Positively charged subatomic particle found in an atom's nucleus.

Hint 28

p. 20

Front 29

radioactive decay

Back 29

An atom emits energy as subatomic particles and x-rays as its unstable nucleus disintegrates spontaneously. The process transforms one element into another.

Hint 29

p. 21

Front 30

radioisotope

Back 30

Isotope with an unstable nucleus (too many or too few neutrons).

Hint 30

p. 21

Front 31

salt

Back 31

blah

Hint 31

p. 29

Front 32

solute

Back 32

blah

Hint 32

p. 27

Front 33

temperature

Back 33

A measure of molecular motion.

Hint 33

p. 26

Front 34

tracer

Back 34

Substance with attached radioisotope that researchers can track after delivering it into a cell, a multicelled body, ecosystem, or other system.

Hint 34

p. 21