Chapter 2: Chemical Basis Of Life

Front 1

the study of matter

Back 1

chemistry

Front 2

occupies space and has mass; (i.e. solids, liquids, gases)

Back 2

matter

Front 3

the smallest particle of an element

Back 3

atom

Front 4

a basic chemical substance composed of atoms

Back 4

element

Front 5

The most abundant of the naturally occurring elements

Back 5

carbon (C), Hydrogen (H), Oxygen (O) and Nitrogen (N) = CHON

Front 6

a positively charged particle in the nucleus of an atom (mass = 1)

Back 6

proton

Front 7

an electrically neutral particle in the nucleus of an atom (mass = 1)

Back 7

neutron

Front 8

an electrically negative particle that revolves around the nucleus (mass = 0)

Back 8

electron

Front 9

represents the number of protons in its nucleus

Back 9

atomic number AN or A#

Front 10

equal to the number of protons plus the number of neutrons in its nucleus

Back 10

atomic weight AW or Mass number MN

Front 11

of an element that have the same A#'s but different AW's

Back 11

isotopes

Front 12

When the nucleus of an atom breaks apart, it releases

Back 12

radioactive energy

Front 13

combining of two or more atoms of the same element

Back 13

molecule

Front 14

combining of two or more atoms of different elements

Back 14

compound

Front 15

number of electrons fill each shell (first 3)

Back 15

-2 electrons fill the first shell (closest to nucleus);
-8 electrons fill the second shell;
-8 electrons fill the third shell.

Front 16

The way in which atoms react with one another (i.e. their chemical properties) is based on the electrons in their outermost shell

Back 16

valence electrons

Front 17

Atoms form bonds with other atoms to

Back 17

fill their outermost or valence electron shell (energy level)

Front 18

atoms that have lost or gained electrons to fill their valence shell

Back 18

ions

Front 19

a negatively charged ion (Cl-)

Back 19

anion

Front 20

a positively charged ion (Na+)

Back 20

cation

Front 21

a bond that is formed by the equal sharing of electrons between atoms

Back 21

covalent bond

Front 22

a bond that is formed by the unequal sharing of electrons between atoms

Back 22

polar bond

Front 23

example of ionic bond

Back 23

Salts, such as table salt or sodium chloride

Front 24

example of covalent bond

Back 24

H2 (molecular hydrogen);
O2 (molecular oxygen);

Front 25

example of polar bond

Back 25

H20 (water)

Front 26

a weak bond formed between hydrogen atoms (that are covalently bonded to another atom) and another atom

Back 26

hydrogen bond

Front 27

example of a hydrogen bond

Back 27

Examples include interaction between water molecules and DNA chains

Front 28

bonds are easily broken and put back together

Back 28

hydrogen bond

Front 29

occurs whenever chemical bonds are formed, rearranged or broken

Back 29

chemical reaction

Front 30

the building of a large molecule (polymer) from smaller building blocks (monomers)

Back 30

Synthesis

Front 31

breaking a large molecule (polymer) down into its building blocks (monomers)

Back 31

decomposition

Front 32

involve degradation followed by synthesis.

Back 32

Exchange Reactions

Front 33

products can be changed back to reactants

Back 33

reversible reactions

Front 34

Acids dissociate (ionize) in water to form

Back 34

a. a hydrogen cation, H+, and
b. an anion.
c. Example = HCl (hydrochloric acid).

Front 35

Bases dissociate (ionize) in water to form

Back 35

a a hydroxyl anion, OH-, and
b. a cation.
c. Example = NaOH (sodium hydroxide).

Front 36

Salts dissociate (ionize) into ions when dissolved in water

Back 36

-an anion is formed and
-a cation is formed.
-Example = NaCl in water.

Front 37

determine the pH in our blood, fluids, and tissues

Back 37

relative concentrations of hydrogen ions and hydroxyl ions

Front 38

pH < 7.4

Back 38

acidosis; lethal below 7.0

Front 39

pH > 7.4

Back 39

alkalosis; lethal above 7.8

Front 40

(are compounds added to solutions that) prevent abrupt change in pH

Back 40

buffers

Front 41

small compounds that do not contain the atoms C and H

Back 41

Inorganic Substances

Front 42

contains the atoms carbon (and hydrogen);

Back 42

Organic Substances

Front 43

usually involved in the formation and breakage of bonds between monomers

Back 43

water

Front 44

The four major classes found in cells

Back 44

a. carbohydrates;
b. lipids;
c. proteins;
d. nucleic acids

Front 45

Monomers (building blocks) are

Back 45

monosaccharides

Front 46

monosaccharides are

Back 46

a. glucose,
b. fructose,
c. galactose

Front 47

2 monosaccharides covalently bonded together

Back 47

Disaccharides

Front 48

Disaccharides are

Back 48

1. maltose = glucose + glucose;
2. lactose = glucose + galactose;
3. sucrose = glucose + fructose

Front 49

many glucose molecules covalently bonded together

Back 49

Polysaccharides

Front 50

Polysaccharides are

Back 50

1. starch = plant storage carbohydrate;
2. glycogen = animal storage carbohydrate; stored in liver and skeletal muscle

Front 51

DEOXYRIBONUCLEIC ACID

Back 51

DNA

Front 52

CARBOHYDRATES contains

Back 52

C, H, and O in a 1:2:1 ratio (usually)

Front 53

LIPIDS contains

Back 53

C, H, and O, but much less O than in carbohydrates

Front 54

a. have only single bonds between the carbons in their fatty acid chains;
b. are solid at room temperature;
c. are animal fats;
d. include bacon grease, lard, butter;
e. are nutritionally "BAD" fat

Back 54

saturated fats

Front 55

a. have one or more double bond between the carbons in their fatty acid chains;
b. are liquid at RT (oils);
c. are plant fats;
d. include corn and olive oil,
e. are nutritionally "GOOD" fat

Back 55

unsaturated fats

Front 56

contains all necessary information needed to sustain and reproduce life

Back 56

DNA

Front 57

Ribonucleic Acid

Back 57

RNA