Chapt. 2

Front 1

chemistry

Back 1

the science that investigates matter and its interactions.

Front 2

elements

Back 2

all matter is composed of substances

Front 3

atom

Back 3

the smallest, stablest unit of matter

Front 4

protons

Back 4

have a positive charge

Front 5

neutrons

Back 5

have a neutral charge

Front 6

electrons

Back 6

have a neg. electrical charge

Front 7

atomic number

Back 7

the number of protons in an atom

Front 8

nucleus

Back 8

is located near the center of the atom

Front 9

electron cloud

Back 9

in a hydrogen atom,a single electron orbits the space around the nucleus at high speed

Front 10

electron shell

Back 10

the cloud is usually rep. as spherical

Front 11

isotopes

Back 11

an atom where it can differ in the number of neutrons in the nucleus

Front 12

mass number

Back 12

the total number of protons and neutrons in the nucleus

Front 13

atomic weight

Back 13

the average mass of an elements atoms

Front 14

chemical bonds

Back 14

hold participating atoms together once the reaction has ended

Front 15

molecules

Back 15

chemical structures that contain more than one atom bonded together by shared electrons

Front 16

compound

Back 16

a chemical substance made up of atoms of two or more elements, regardless of the type of bond joining them

Front 17

ions

Back 17

atoms or molecules that have an electric charge

Front 18

cations

Back 18

ions with a positive charge

Front 19

anions

Back 19

ions with a negative charge

Front 20

ionic bonds

Back 20

chemical bonds created by the electrical attraction between anio s and cations

Front 21

covalent bonds

Back 21

let's atoms fill their outer electric shell is by sharing electrons with other atoms

Front 22

single covalent bond

Back 22

the two hydrogen atoms share their electrons, with each electron whirling around both nuclei.

Front 23

double covalent bond

Back 23

oxygen atoms become stable by sharing two pairs of electrons

Front 24

nonpolar covalent bonds

Back 24

when the electrons are shared equally, the bound atoms remain electrically neutral

Front 25

polar covalent bond

Back 25

an unequal sharing between atoms of different elements

Front 26

hydrogen bond

Back 26

the attraction between between a slight positive charge on the hydrogen atom of one polar covalent bond and a weak neg. charge on an oxygen or nitrogen atom or another polar covalent bond

Front 27

decomposition reaction

Back 27

breaks a molecule into smaller fragments

Front 28

hydrolysis

Back 28

one of the bonds in a complex molecule is broken and the components of a water molecule is broken

Front 29

catabolism

Back 29

the decomposition reactions of complex molecules within cells

Front 30

synthesis

Back 30

the opposite of decomposition

Front 31

dehydration synthesis

Back 31

the formation of complex molecule by the removal of water

Front 32

anabolism

Back 32

the synthesis of new compounds in the body

Front 33

exchange reaction

Back 33

AB + CD = AD + CB

Front 34

equilibrium

Back 34

the rates of two reactions are in balance

Front 35

activation energy

Back 35

the amount of energy required to start a reaction

Front 36

enzymes

Back 36

speed up the reactions that support life

Front 37

catalysts

Back 37

accelerate chemical reactions without themselves being g permanently changed

Front 38

exergonic

Back 38

reactions that release energy

Front 39

endergonic

Back 39

the reactions as a whole will absorb energy

Front 40

nutrients

Back 40

the essential elements and molecules obtained from a diet

Front 41

inorganic compounds

Back 41

small molecules that generally do not contain carbon and hydrogen atoms

Front 42

organic compounds

Back 42

primarily composed of carbon and hydrogen atoms

Front 43

solutions

Back 43

consist of a uniform mixture of a fluid solvent and dissolved solutes

Front 44

dissociation

Back 44

inorganic compounds held together by ionic bonds

Front 45

ionization

Back 45

dissociation

Front 46

acid

Back 46

any substance that breaks apart in solution to release hydrogen ions

Front 47

base

Back 47

a substance that roves hydrogen ions from a solution

Front 48

electrolyte

Back 48

inorganic compounds whose ions can conduct an electrical current in solution

Front 49

buffers

Back 49

compounds that stabalize pH by either removing or replacing hydrogen ions

Front 50

carbohydrate

Back 50

an inorganic molecule that contains carbon, hydrogen, and oxygen in a ratio near 1:2:1

Front 51

simple sugar (monosaccharide)

Back 51

a carb containing from 3 to 7 carbon atoms

Front 52

glucose

Back 52

the most important metabolic fuel in the body

Front 53

disacharide

Back 53

two monosaccarides formed together

Front 54

polysaccharides

Back 54

result when repeated dehydration synthesis reactions add additional monosaccharides or disaccharides

Front 55

glycogen (animal starch)

Back 55

a polysaccharide composed of interconnected glucose molecules

Front 56

lipids (fats)

Back 56

contain carbon, hydrogen, oxygen

Front 57

fatty acids

Back 57

long chains of carbon atoms with attached hydrogen atoms that end in a carboxyl group

Front 58

saturated

Back 58

four single covalent bonds of each atom permit each neighboring carbon to link to each other and to two hydrogen atoms

Front 59

unsaturated

Back 59

fewer hydrogen atoms are present

Front 60

triglyceride

Back 60

a glycerol molecule is attached to 3 fatty acids

Front 61

steroids

Back 61

large lipid molecules composed of four connected rings of carbon atoms

Front 62

cholesterol

Back 62

best known steroid

Front 63

phospholipid

Back 63

consists of a glycerol and two fatty acids linked to a nonlipid group by a phosphate group

Front 64

protein function

Back 64

1 support
2 movement
3 transport
4 buffering
5 metabolic regulation
6 coordination and control
7 defense

Front 65

antibodies

Back 65

protect us from disease

Front 66

clotting proteins

Back 66

restrict bleeding following an injury to the cardiovascular system

Front 67

amino acids

Back 67

proteins are long chains of organic molecules called -

Front 68

peptide bond

Back 68

the individual amino acids are strung together like beads on a string, with the carboxyl group of one amino acid attached to the amino group of another

Front 69

peptides

Back 69

molecules made up of amino acids held together by peptide bonds

Front 70

substrates

Back 70

the reactants in an enzyme reaction

Front 71

product

Back 71

outcome

Front 72

active site

Back 72

the substrates must bind a special region of the enzyme called-

Front 73

nucleic acids

Back 73

large organic molecules somposed of carbon, hydrogen, oxygen, nitrogen, and phosphorus

Front 74

deoxyribonucleic acid

Back 74

DNA

Front 75

ribonucleic

Back 75

RNA

Front 76

high energy compound

Back 76

a high energy bond usually connects a phosphate group to an organic molecule

Front 77

adenine triphospate

Back 77

ATP

Front 78

adenine diposphate

Back 78

ADP