Chemistry in Biology

Lesson 2

bulk elements

required by the body in large amounts

C,O,H,N,S,P

trace elements

required by the body in small amounts

Fe, I

ultratrace elements

required by the body in very minute amounts

As

matter

anything that occupies space

mass

the amount of matter in an object

weight

the gravitational force acting on an object of a given mass

element

the simplest type of matter with unique chemical properties

composed of atoms of only one kind

atom

smallest particle of an element that has chemical characteristics of that element

smallest unit of matter

composed of subatomic particles

neutron

no electrical charge

protons

one positive charge

electrons

one negative charge

protons and neutrons

what forms the nucleus of an atom

electron

which is the smallest subatomic particle in an atom

protons

an elements atomic number represents the number of _____ in that atom

atomic weight

average mass of naturally occurring isotopes of element/atom

protons + neutrons

formula for atomic weight

isotope

different kind of atom of the same element where the number of neutrons in the nucleus varies

sometimes radioactive

molecule

particle formed when two or more atoms chemically combine

compound

particle formed when two or more atoms of different elements chemically combine

molecular formulas

depict the elements present and the number of each atom present

molecular mass

determined by adding up atomic masses of its atoms or ions

structural formulas

show how atoms bond and are arranged in various molecules

chemical bonds

form when atoms combine with other atoms

result from interaction between the electrons of the atoms

valence shell

outermost electron shell

highest energy

valence electrons

electrons that form chemical bonds

ionic bonding

atoms exchange electrons

one loses and one gains

becomes charged

covalent bonding

two or more atoms share electron pairs

ionic bonds

what bond is between metals and nonmetals

covalent bonds

what bond is between two nonmetals

anion

negatively charged ion

atom that gained one or more electrons

cation

positively charged ion

atom that lost one or more electrons

polar and nonpolar

what are the two types of covalent bonds

nonpolar

do polar or nonpolar covalent bonds share electrons equally

polar

do polar or nonpolar covalent bonds share electrons unequally

negative

the atom that attracts the electrons more strongly in a polar covalent bond carries a patrial _____ charge

positive

the atom deprived of electrons in a polar covalent bond carries a partial _____ charge

polar

is water polar or nonpolar

polar

molecules with a O or N are usually polar or nonpolar

hydrogen bonds

attractive force between electropositive hydrogen of one molecule and an electronegative atom of another molecule

not a true bond

synthesis reaction

A + B → AB

decomposition reaction

AB → A + B

exchange reaction

AB + CD → AD + CB

reversible reaction

A + B ←→ AB

oxidation

loss of an electron by a substance

reduction

gain of an electron by a substance

oxidation-reduction reaction

the complete or partial loss of an electron by one substance is accompanied by the gain of that electron by another substance

activation energy

minimum energy reactants must have to start a chemical reaction

catalysts

substances that increase the rate of chemical reactions without being permanently changed or depleted

enzymes

protein catalysts that increase the rate of chemical reactions

electrolytes

substances that release ions in water

the solution can conduct an electric current

acids

electrolytes that dissociate to release hydrogen ions in water

HCl

bases

substances that release ions that can combine with hydrogen ions

NaOH

salts

electrolytes formed by the reaction between an acid and a base

acidic

pH<7

neutral

pH=7

basic

pH>7

acids

do acids or bases have a higher concentration of hydrogen ions

7.35-7.45

what is the normal range of blood pH

acidosis

occurs when blood pH drops to 7.0-7.3

makes a person feel disoriented, fatigued

alkalosis

occurs when blood pH rises to 7.5-7.8

makes a person feel dizzy and agitated

buffers

chemicals which act to resist pH changes

act as conjugate acid-base pair

bicarbonate, phosphates, proteins

inorganic substances

water, salts, and many acids and bases

do not contain carbon

organic substances

carbohydrates, fats, proteins, and nucleic acids

contain carbon, usually large, and and covalently bonded

organic inorganic

all chemicals are either ____ or ____

inorganic

water, oxygen, carbon dioxide, and inorganic salts are all

carbohydrates

lipids

proteins

nucleic acids

what are the four types of organic molecules

monomers

building blocks

polymers

chains of monomers

monosaccharides

monomers of carbohydrates

C, H, O

what atoms are found in carbohydrates

disaccharide

consist of two linked monosaccharides

polysaccharides

long chains (polymers) of linked monosaccharides

cellulose

lipids

fats

unsoluble in water

C, H, O, P

what atoms are found in lipids

lipids

the are all types of what

triglycerides

steroids

phospholipids

eicosanoids

triglyceride

important in energy, insulation, and protection

three fatty acid chains are bound to glycerol by dehydration synthesis

saturated fatty acids

have only single carbon-carbon bonds

most are solid at room temperature

animal origin

solid fats

unsaturated fatty acids

have one or more carbon-carbon double bond

most are liquid at room temperature

plant origin

oils

phospholipid

two fatty acid chains and a phosphorous containing group are attached to the glycerol backbone

steroids

formed by four interlocking hydrocarbon rings

eicosanoids

many different ones

derived from a fatty acid (arachidonic acid) in cell membranes'

prostaglandins

C, H, O, N, S

what atoms are found in proteins

proteins

structural support, energy source, chemical messengers, receptors, antibodies, transporter, hormones, contractions, regulators, enzymes

amino acids

make up proteins

peptide bonds

what links amino acids together

primary structure

protein structure that is the amino acid sequence

secondary structure

protein structure that results from hydrogen bonding between amino acids

pleated (folded) sheets

tertiary structure

protein structure with large scale folding due to interactions within protein and surrounding environment

quaternary structure

protein structure that results from the association of two or more proteins

primary

secondary

tertiary

quaternary

what are the four protein structures

nucleotides

nucleic acids are made from

nucleic acids

chemical structures that form genes to carry out instructions for cell activities

C, H, O, N, P

what atoms are found in nucleic acids

phosphodiester bond

bond between 2 nucleotides

nucleotide

composed of a five-carbon sugar, a phosphate, and a nitrogenous base

pyrimidines

contain only one ring

cytosine, thymine, uracil

purines

contain two rings

guanine, adenine

C-G

A-T

what are the base pairings in DNA

C-G

A-U

what are the base pairings in RNA

ATP

nucleic acid

energy currency of the body