A&P: Chapters 2.1-2.5

matter

anything that has weight and occupies space

mass

the amount of matter present in a substance or object

chemistry

the science of the composition and interactions of matter

atom

smallest particle of an element that has the properties of that element

electron

extremely small particle within an atom; almost no weight; carries a negative electrical charge and is in constant motion around an atomic nucleus

neutron

relatively large particle within an atom; about the same weight as a proton; uncharged and thus electrically neutral; found within an atomic nucleus

proton

relatively large particle within an atom; carries a positive elctrical charge and is found within an atomic nucleus

molecule

particle formed by the chemical union of two or more atoms

elements

any of the fundamental chemical substances, each characterized by a distinct type of atom

compound

substance composed of two or more chemically bonded elements

bulk element

basic chemical required in abundance

trace element

basic chemical substance needed in small quantity

ultratrace element

basic chemical substance needed in very small quantity

biochemistry

a branch of chemistry that focuses on the chemistry of living organisms

atomic radiation

the energy or fragments of matter emitted from the unstable nuclei of certain isotopes, such isotopes with unstable nuclei are called radioactive isotopes

atom

smallest particle of an element that has the properties of that element

chemical bonds

attractive force that can hold atoms together

nucleus

composed of protons and neutrons: enclosed by a double bilayer nuclear envelope and containing DNA

atomic number

number of protons in an atom of an element

mass number

total number of protons and neutrons in the nucleus of an atom

isotope

atom that has the same number of protons in its nucleus as other atoms of that element but has a different number of neutrons

atomic weight

number of protons plus the number of neutrons in an atom of an element

molecule

particle composed of two or more joined atoms

molecular formula

abbreviation for number of atoms of each element in a compound

bond

connection between atoms in a molecule

electron shell

the space occupied by an electron or several electrons encircling the nucleus of an atom at a particular energy level

inert

elements that do not react with other elements

ions

electrically charged atom or molecule

cations

atom or molecule carrying a net positive charge due to a deficiency of electrons

anion

atom or molecule carrying a net negative charge due to one or more extra electrons

ionic bond

chemical bond that results between two ions formed by transfer of elctrons; electrovalent bond

covalent bond

chemical bond formed by electron sharing between atoms

structural formula

representation of the way atoms bond in a molecule, using symbols for each element and lines to indicate chemical bonds

nonpolar covalent bonds

covalent bond where the electrons are shared equally between the atoms

polar

a molecule with equal numbers of protos and electrons, yet having a slightly positive region and a slightly negative region due to uneven distribution of those charged particles

hydrogen bond

weak bond between a hydrogen atom and an atom of oxygen or nitrogen

reactant

a chemical that takes part in a chemical reaction, a starting material

product

the result of a chemical reaction

synthesis

building large molecules by bonding smaller ones

decomposition

the breakdown of molecules

reversible reaction

chemical reaction in which the products can react, yielding the original reactants

catalyst

chemical that increases the rate of a chemical reaction, but is not permanently altered by the reaction

exchange reaction

chemical reaction in which parts of two types of molecules trade positons

electrolyte

substance that ionizes in a water solution dissociate: the process by which molecules split into ions when placed in water

acid

substance that releases hydrogen ions

base

substance that releases ions that can combine with hydrogen ions

salt

substance formed by the reaction between an acid and a base

pH scale

shorthand notation for the hydrogen ion concentration used to indicate the acidic or alkaline condition of a solution; range is 0 to 14

acidic

a solution with a pH less than 7.0

alkaline (basic)

a solution with a pH greater than 7.0

alkalemia

a blood pH above 7.5

alkalosis

increase in the pH of body fluids above 7.5

acidemia

a blood pH below 7.3

acidosis

decrease in the pH of the body fluids below pH 7.53

water (H2O)

inorganic substance; most abundant compound in living material. it’s a major component of blood and other body fluids, including fluids in cells

oxygen (O2)

molecules enter the internal enviroment through the respiratory organs and are carried throughout the body by the blood, especially by red blood cells.

carbon dioxide (CO2)

a simple, carbon-containing inorganic compound. a waste product of the release of energy during certain metabolic reactions

nitric oxide (NO)

involved in digestion, memory, immunity, respiration, and circulation

carbon monoxide (CO)

functions in the spleen, which recylces old red blood cells, and is in the parts of the brain that control memory, smell, and other vital functions

inorganic salts

abundant in body fluids, they are the sources of many necessary ions, including ions of sodium, chloride, potassium, calcium, magnesium, phosphate, carbonate, bicarbonate, and sulfate.

these play important roles in metabolism, helping to maintain proper water concentrations in body fluids, controlling pH, blood clotting, bone development, energy trasnfer in cells, and muscle and nerve functions.

carbohydrate

organic compound, consisting of carbon, hydrogen, and oxygen. provides much of the energy that cells require

sugar

sweet tasting carbohydrate

monosaccharide

single sugar, such as glucose or fructose

disccharide

sugar produced by the union of two monoschcharides

polysaccharide

carbohydrate composed of many joined monosaccharides

lipids

a group of organic chemicals that are insoluble in water but soluble in organic solvents, such as ether and acetone. group of organic compounds that includes fats, phospholipids, and steroids

triglyceride

lipid composed of three fatty acids and a glycerol molecule; fat

fat

an organic molecule that includes glycerol and fatty acids; adipose tissue

fatty acids

one of the building blocks of a fat molecule

glycerol

organic compound that is a building block for fat molecules

saturated fatty acid

fatty acid molecule that includes a maximal number of hydrogen atoms and therefore has no double-bonded carbon atoms

phospholipid

molecule consisting of two fatty acids and a phosphate group to a glycerol molecules

steroid

type of organic molecule including complex rings of carbon and associated hydrogen and oxygen atoms

proteins

nitrogen-containing organic compound composed of many bonded amino acid molecules

enzyme

protein that catalyzes a specific biochemical reaction

amino acid

organic compound that includes an amino group; the structural unit of a protein molecule

conformation

three-dimensional structure of a protein, determined by its amino acid sequence and attractions and repulsions between amino acids in different parts of the molecule

nucleic acid

a molecule that is composed of bonded nucleotides; RNA or DNA

nucleotide

building block of a nucleic acid molecule, consisting of sugar, nitrogenous base, and phosphate group

RNA

ribonucleic acid, composed of nucleotides that have ribose sugar

DNA

deoxyribonucleic acid; the genetic material