Middle School Science questions – Flashcards

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technology
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the application of science through the use of special procedures or devices
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dependent variable
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a variable that is not under the expirementer's control
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constant
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not changing or varying
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meter
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a standard of measurement equal to a little over a yard
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metric
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a standard of measurement
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millimeter
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a standard of measurement equal to one thousandth of a meter
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centimeter
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a standard of measurement equal to one hundredth of a meter
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decimeter
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a standard of measurement equal to one tenth of a meter
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kilometer
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a standard of measurement equal to one thousand meters
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Celsius
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metric temperature scale on which water freezes at 0 degrees and boils at 100 degrees
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Farenheit
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tempurature scale on which water freezes at 32 degrees and boils at 212 degrees
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law
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a statement of scientific fact
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theory
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an idea based on speculation
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hypothesis
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a theory which needs further investigation
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volume
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the space inside of an object
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mass
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the amount of matter an object contains
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property
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a trait or attribute
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control
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the standard against which experimental test results are compared
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density
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a measure of a quantity of mass per unit of volume
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lipid
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any group of organic compunds consisting of fats, oils, and related substances; a part of the structural components of a living cell
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monomer
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a single organic molecule that can join in long chains with other molecules
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amino acid
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nitrogen-containing organic molecules that from the basic buliding units of proteins
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nucleic acid
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a complex acid found in living cells
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aromatic
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a class of organic chemical compounds that contains one or more rings of carbon atoms
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polymer
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a compound with repeating small molecules such as starch and nylon
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petroleum
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crude oil found in sedimentary rocks and consisting mainly of hydrocarbons
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synthetic
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a substance made by a chemical process
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hydrocarbon
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an organic chemical containing only hydrogen and carbon
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organic compound
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elements that exist together naturally without synthetic chemicals
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saturated
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containing the maximum amount of absorbed solvent
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unsaturated
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having double or triple carbon atoms
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DNA (deoxyribonucleic acid)
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substance carrying an organism's genetic information
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density
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a measure of quantity such as mass or electric charge per unit volume
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solvent
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a substance in which other substances are dissoloved
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freezing point
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the temperature at which a liquid becomes a solid
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alloy
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any mixture of two or more materials
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antifreeze
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a liquid that lowers the freezing point
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solubility
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the capacity for one substance to dissolve another
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supersaturated
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a chemical solution that contains a greater amount of solute than normally possible, often as a result of cooling
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electrolyte
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a chemical compound which separates into ions in a solution
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ionization
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a process in which an atom or molecule loses or gains electrons
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dissociation
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the process by which an ionic solid will separate into its ions in a solution
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ion
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an electrically charged atom or atom group
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positive ion
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an atom missing one or more of its electrons
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covalent
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a chemical bond between two atoms created by sharing a pair of electrons
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neutral
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with zero electric charge
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formula
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a set of symbols representing chemical composition
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oxidation number
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the number of associated electrons in a compound
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polar molecule
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chemical compund with an unequally distributed electric charge
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nonpolar
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chemical compunds with an equally distributed electric charge
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hydrate
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a compound containing water molecules
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bond
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an attractive force that binds atoms and ions in a molecule
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ductile
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moldable, as in the characteristic of metals
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radioactive
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the emission of energy in the form of streaming particles by substances such and uranium or plutonium
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transition element
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an element in groups of three through twelve of the periodic table
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semiconductors
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a partially conductive solid
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transuranium
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having an atomic number over 92
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allotropes
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one of several different forms in which a chemical element occurs, each with different physical properties but the same atomic compostion
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sublimation
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a chemical process in which a solid is directly converted to a gas
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diatomic
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having two atoms per molecule
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ionic
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relating to matter in the form of charged atoms or groups of atoms
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metallic
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containing or made of metal
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alkali
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a chemical substance that is water soluble, neutralizes acid, and forms salts with them
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noble gas
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a chemically non-reactive gas
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distillation
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the process of separating a mixture by evaporation and condensation
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colloid
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a suspension of small particles dispersed in another substance
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solution
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the state of one substance being dissolved in another substance
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mixture
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a substance containing several ingredients which have been blended together
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Tyndall effect
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the scattering of light by minute particles in its path, such as dust in the air
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compound
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a substance made by combining two or more different elements
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suspension
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a dispersion of fine solid particles in a liquid
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heterogenous
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a chemical substance consisting of different and distinguishable materials
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element
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a substance that can not be broken down into a simpler one by a chemical reaction
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tungsten
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a specific metallic chemical element with a very high melting point
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proton
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a stable, elementary particle that is a component of all atomic nuclei; carries a positve charge equal to that of the electron's negative charge
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atomic number
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the number of protons in the nucleus of an atom of an element
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isotope
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a form of an element with the same atomic number
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periodic table
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a table of chemical elemetns arranged according to their atomic numbers
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neutron
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an elementary particle without an electric charge
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electron
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a stable, negatively charged elementary particle with a small mass that is a basic ingredient of matter and orbits the nucleus of an atom
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quark
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a basic component of particles
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metalloid
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a nonmetallic element that had properties between those of a metal and a nonmetal
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particle
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a basic unit of matter; a molecule, atom, or electron
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nitrogen
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an element common in the Earth's atmosphere
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metal
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a chemical element that is usually a shiny solid and conducts heat or electricity
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machine
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a device that makes work easier to preform
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simple machine
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any device that only requires the application of a single force to work
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Ideal Mechanical Advantage (IMA)
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the factor by which a machine multiplies the force put into it
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device
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a tool or machine which perfroms a particular task or function
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gear
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a toothed wheel that enagages another toothed mechanism in order to transmit motioin from one rotating body to another
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efficiency
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the measure of a machine's energy effectiveness
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wheel and axel
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a simple machine consisting of a large wheel rigidly secured to a smaller wheel or shaft, called an axel
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ramp
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a sloped surface used to move from one level to another
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screw
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a simple machine of the inclined-plane mtype consisting of a spirally threaded, cylindrical rod that engages into a similarily threaded hole
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James Watt
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engineer and inventor whose improvements of the steam engine led to its wide use in industry
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lever
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a rigid bar that pivots around a fulcrum and is used to move or lift a heavy load at one end by applying force to the other
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wedge
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a block that is thick at one end and thinner at the other, used to secure or separate two objects
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pulley
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a wheel with a grooved rim over which a belt or chain or chain can move to change the direction of a pulling force
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fulcrum
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th point about which a lever turns
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inclined plane
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slanted surface used to raise or lower an object
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pivot
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an object on which a larger object turns
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output force
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energy or power produced by a system
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input force
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power or energy that enters a device and is recovered in the form of work or some other output effect
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applied force
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a force which is applied to an object by a person or another object
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expand
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to cause something to increase in size or volume as a result of a rise in temperature or a decrease in pressure
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buoyant force
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a force that causes objects in a liquid to float or rise to the surface or upward in gas
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Archimedes
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Greek mathemetician, physicist, and inventor, best known for the lever and the pulley
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viscosity
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the property orf a fluid that resists flowind
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diffusion
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the random movement of atoms, molecules, or ions, from one site in a medium to another, resulting in complete mixing
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sublimation
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the change of ice to vapor or vapor to ice without a liquid stage
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kilocalorie
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a unit of energy equal to a nutritional calorie
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boiling point
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the degree of temperature at which a liquid turns to gas
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heat of fusion
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the heat released when liquid water freezes to solid ice
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plasma
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a hot ionized gas made up of ions and electronsfound in the sun, stars, and fusion reactors
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pascal
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a unit of pressure equal to one newton per square meter
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SI unit
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a unit of measure in the International System of Units
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compressed
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redused in volume by pressure
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solid
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a substance that retains its shape
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liquid
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a substance whose shape can change but whose volume cannot
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gas
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a substance that is neither a solid nor a liquid and that has the ability to expand
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redox
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an abbreviation for oxidation-reduction, a process in which there is an electron transfer
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precipitate
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a suspension of small solid particles formed in a solution as the result of a chemical reaction
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reactant
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a substance undergoing a chemical reaction
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Antoine Lavoisier
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French chemist know as the "father" of modern chemistry
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exothermic
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a reaction that produces heat
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endothermic
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a reation that abosorbs heat
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decompostion
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chamical change in which a substance is broken down into two or more simpler substances
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combustion
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process in which a substance reacts forcefully with oxygen to produce heat and light
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catalyst
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a chemical that increases the rate of a chemical reaction
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corrosion
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process in which a substance, such as metal, is destroyed gradually by a chemical action
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reduction
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a chemical reaction which brings about a grain in hydrogen, a loss in oxygen, or an increase in electrons
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synthesis
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the process of forming a complex compound from a chemical reaction involving two or more simpler elements
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endergonic
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a chemical reaction in which energy is abosorbed
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acid
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a corrosive substance with a pH less than seven; turns blue litmus paper red
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ammonia
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a colorless, pungent, water soluble gas made up of nitrogen and hydrogen
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indicator
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an organic compund that changes color in acid or base
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titration
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a way of determining the concentration of a solution
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base
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a chemical compound having pH between eight and fourteen; reacts with acids to form salts
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pH
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a measure of acidity or alkalinity
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buffer system
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a substance that minimizes a change in the pH of a soluton by neutralizing added acids and bases
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polyester
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a synthetic polymer used in making textile fibers
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detergent
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a cleansing substance, especially a synthetic liquid that dissolves dirt and oil
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hydronium
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the positive ion containing three hydrogen and one oxygen formed when an acid dissolves in water
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saponification
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the reaction of an ester with metallic base and water which produces soap
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neutralization
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the addition of substances to neutralize water so that it is neither acidic nor alkaline
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compressional wave
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a wave that moves in the same direction as the periodic motion of the medium
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frequency
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the number of wavelengths that passes a fixed pont every second
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amplitude
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the measurement of the height of a transverse wave
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transverse wave
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a wave that cause the crosswise disturbance of a medium
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interference
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process in which two or more waves overlap and combine to form a new wave
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rarefaction
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the less dense region of a compressional wave
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refraction
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the change in direction that occurs when a light wave passes from medium to another of a different density
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standing wave
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a stationary wave which occurs when two waves of equal frequency and intensity traveling in oppostite directions combine
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acoustics
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the scientific study of sound
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decibel
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a unit of relative loudness
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resonator
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a hollow chamber filled with air that amplifies sound
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echolocation
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a way of locating an object using an emitted sound and the reflection back from it
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overtone
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frequencies which are multiples of the lowest or main frequency
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oscilloscope
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a device that uses a cathode ray tube to show waveforms
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diffuse reflection
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1light that scatters in all directions when it strikes a rough surface
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pigment
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colored material used to change the colors of other substances
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reflecting telescope
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a telescope in which light from the object is initially focused by a concave mirror
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opague
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not allowing light to pass into or through something
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prism
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a glass object that can separate white light into a spectrum
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optical axis
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an imaginary line passing horizontally through the center of a compound lens system
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cone cells
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the cells in the retina which only function in relatively bright light
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polarize
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to cause light to vibrate within certain planes
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astigmatism
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an optical lens defect in which light rays are prevented from meeting at a single pont, producing an imperfect image
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incandescent
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a light emitted as a result of being heated to a high temperature
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focal point
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the point where rays from a lens converge
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retina
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a light-sensitive membrane in the back of the eye that receives an image from the lens and sends it to the brain
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coherent light
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light waves that vibrate with constant phase relationships that are produces by a laser or a combination of two prisms
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laser
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a device which emits a focused beam of light
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parallel circut
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a closed circut in which the current divides into two or more paths before recombining to complete the circut
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resistance
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the tendancy for a material to oppose the flow of electrons
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electroscope
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a device used to detect and measure an electric charge
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ampere
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the SI unit of electric charge
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ohm
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the SI unit of electrical current
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watt
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the SI unit of power
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volt
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the unit of electromotive force and electric potential
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filament
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a thin wire conductor in a light bulb
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series circut
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a circut through which the electrical current flows in a single continuous path.
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kilowatt
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a unit of electricity equal to 1,000 watts
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static electricity
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a stationary electric charge that builds up on an insulated object
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conductor
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a substance or medium that allows heat, electricity, light, or sound to pass along it or through it
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kinetic energy
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energy that a body possesses becasue of its motion
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transformer
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a device that changes electrical energy from one alternating circut to another
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electromagnetic
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a soft metal core made into a magnet by the passage of electricity through a coil surrounding it
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solenoid
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a type of electromagnetic constructed so that the core moves, usually linearly, when electricity is passed through it
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magnetic field
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a space surrounding a magnetized body or current-carrying circut
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aurora
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a phenomenon occuring in the night sky around the polar regions, caused by gases in the atmosphere which interact with solar particles
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compass
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a device for finding direction which uses a magnetized needle that automatically swings to the magnetic north
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magnetic domain
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a small, magnetized region of a magnetic surface
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galvanometer
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an instrument used to measure electric current by means of a coil in a magnetic field that moves a pointer or light
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polarity
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the quality or having two oppositely charges poles, one positive and one negative
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magnet
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a piece of metal that has the power to draw iron or steel objects toward it and to hold or move them
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transmutation
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the process that changes one element into another through nuclear delay
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srong force
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the force that holds particles together in a nucleus
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alpha particle
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a positive particle consisting of 2 protons and 2 neutrons; the nucleus of a helium atom
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alpha radiation
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the least-penetrating type of radiation; can be stopped by a sheet of paper
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cloud chamber
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a device used to detect the movement of high energy particles as they pass through a chamber of supersaturated vapor
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Geiger counter
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a device used to detect and measure radiation
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beta particle
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an electron created by radioactive emission
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tracer
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a radioactive isotope that can be detected by the radiation it emits
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bubble chamber
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a chamber in which the trail of a particle can be observed as a line of bubbles created by a particle
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chain reaction
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a series of nuclear reactions in which neutrons produced by a fission cause more friction
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displacement
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the amount of movement in a particular direction
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force
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a physical influence that tends to change the postion of an object with mass
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inertia
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the tendancy for a body at rest to stay at rest, or a body in motion to stay at motion, unless acted upon by a force
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friction
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resistance encountered by a moving object
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static friction
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resistance between two objects that are in contact but are not moving
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sliding friction
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the frictional resistance an object in motion experiences
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velocity
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the speed at which something moves or happens
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acceleration
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the rate at which something increases in velocity
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centripetal
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moving or pulling toward a center or axis
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gravity
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the force that tends to pull all bodies in Earth's sphere toward the center of the Earth
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calculus
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a branch of mathematics that studies continuously changing quantities
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air resistance
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the force of air pushing against a moving object
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weight
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the gravitational force exerted on a mass
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momentum
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the motion of a body and its resistance to slowing down
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matter
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a substance or material of a particular kind
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photovoltaic
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a photoelectric cell that detects and measure light intensity
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solar thermal
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the use of radiation from the sun to produce heat energy
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renewable
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an unlimited supply or resource
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fractional distillation
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the separation of components from a volatile liquid that have different boiling points
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turbine
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a machine which uses steam or another fluid in motion to move rotation blades; the rotay motion is then turned into electrical or mechanical power
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generator
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a device that converts mechanical energy into electricity
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biomass
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the mass or organisms in the ecosystem, measured in terms of weight per unit of area
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sedimentary
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used to describe ricks formed from eroded material
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geothermal energy
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the heat energy found below the earth's surface
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fossil fuel
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fuel made from decomposed remains of prehistoric plants and animals
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gamma radiation
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high-energy electromagnetic raditation
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mechanical advantage
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the ratio output force to input force for a machine
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law of conservation of mass
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the scientific law which states that mass can be neither created nor destoyed during a chemical reaction, only changed from one form to another
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decay
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to undergo spontaneous disintergration
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copper
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a reddish brown metallic chemical element that bends easily and is a good conductor of electricty and heat
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aluminum
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a light metallic element that is ductile, malleable, and resistant to corrosion
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focal length
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the distance from the center of a lens to the focal point
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specific heat
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the amount of heat needed to raise the temperature of one gram of substance by one degree
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photosynthesis
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process by which plants use sunlight, carbon dioxide, and water to make food; also produces a large part of the oxygen in the atmosphere
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Linnaeus
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system of naming plants and animals
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nucleus
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the part of a cell which contains genetic material
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carbon dioxide
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a nonpoisonous gas created by respiration and by the decomposition of living organisms
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chloroplasts
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structures in the cells of leaves contain chlorophyll
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endoplasmic reticulum (ER)
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a net-like system within the cytoplasm involved in the synthesis, modification, and transportation of cellular materials
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virus
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an organism that causes an infectious disease
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species
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a group of related organisms sharing common characteristics
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kingdom
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the scientific classifications into which organisms are grouped
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organelles
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compartments within cells that perform specific functions; the nucleus, for example
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mitiosis
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the process by which a cell divides
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meiosis cell
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division that produces reproductive cells
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metaphase
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stage of mitosis when the chromosomes line up along the center of the cell
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anaphase
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stage of mitiosis in which the chromosomes begin to separate
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Punnett square
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tool used to show the potential offspring of two parents
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chromosomes
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a structure in the nucleus of a cell composed of DNA and protein
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phenotype
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the observable characteristics of a cell or organism
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dominent
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gene that determines the characteristics in the organism
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homozygous
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having two identical versions of a specific gene
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heterozygous
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possessing two different forms of a specific gene
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zoologist
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a person who specializes in animal life
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flagellum
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a whip-like structure of a cell responsible for cell movement
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pigment
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a naturally occuring substance in a plant thta gives the plant its color
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bacillus
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a rod-shaped bacterium
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bioremediation
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process used to clean up contaminated land using bacteria and organisms to neutralize soil contaminants
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coccus
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a kind of bacterium with a spherical shape
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fission
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the division of a single-celled organism into two equal parts
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anaerobes
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a microorganism that does not require oxygen for growth
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capsule
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structure that allows bacteria to stick to surfaces
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spirillum
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a spiral-shaped bacterium
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ribosome
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an organelle that produces protein in cells
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cytoplasm
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cellular substance which surrounds the nucleus and holds genetic material
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dinoflagellate
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a single-celled organism found in fresh and marine waters with characteristics of both plants and animals
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fungus
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a plant-like organism which does not make chlorophyll
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protozoan
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a single-celled organism that can move and feed on organic compounds
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mycology
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the specialty of studying fungi
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zygosphere
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a plant spore formed by meiosis
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lichen
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a plant that is a combination of a fungus and an agla; commonly grows on trees or rocks
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protist
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single-celled organism which has an eukarotic cell but is not a member of the plant, fungal, or animal kingdoms
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spore
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an asexual reproductive structure which can produce a new organism; fungi, algae, and many other organisms produce spores rather than seeds
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algae
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simple. rootless plants tha grow in water in proportion of availible nutrients
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chlorophyll
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green pigment found in plants, algae, and some bacteria; needed to aid in the process of photosynthesis
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African sleeping sickness
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disease transmitted by the bite of the tsetse fly
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vascular
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relating to plants with tissues that have the ability to carry fluid
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dicot
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flowering plant whose seedlings have two seed leaves; for example, a bean
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gymnosperm
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a plant with bare seeds, as with the pines, where the seeds are attached at the base of the scales in the cone
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xylem
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a type of plant tissue that carries water and dissolved minerals from the roots through the stem and leaves
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angiosperm
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a flowering plant whose seeds have a covering of some kind, such as a pod or a fruit
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phloem
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food-transporting tissue of a plant; also know as the inner bark
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cone
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the seed-bearing part of pines and firs
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monocot
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a flowering plant whose seedling has only one seed leaf; for example, grass
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cuticle
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the waxy, protective layer which covers the stem, leaves, and flowers of many plants and helps provent water loss
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moss
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small, leafy flowerless plant that grows in moist, shaded areas
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fertilization
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the process of reproduction by pollination
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ovule
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small structure in a seed plant that contains the eggs and, when fertilised by pollen , develpoes into seeds
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stigma
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the part of the flower's female reproductive system taht receives the male pollen grains
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germination
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the beginning growth of a seed or spore
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symbiotic
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a close association between two different species in which both species benefit
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anther
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the part of the flower which produces pollen
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frond
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refers to the leaf structure of ferns or palms
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endosperm
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the tissue of a seed containing the nutrients
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sporophyte
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the spore-producing stage in the life cycle of a plant
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ovary
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the lower part of the pistil that contains immature seeds
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stomata
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tiny pore in the outer layer of a plant leaf that regulates the movement of gases(water vapor and others) between the plant and the atmosphere
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respiration
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process by which energy is released by food
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producer
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an organism which makes its own food
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epidermis
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the outside layer of cells on a plant which helps prevent injury
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mitochondrion
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energy-producing cellular organelles found outside the nucleus that convert food to energy
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tropism
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plant growth toward or away from an environmental stimulus such as heat or light
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stimulus
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the cause of physical response in an organism
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hormones
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a regulating chemical in plants
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vacuole
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a space in the cytoplasm of a cell which stores food and fluid
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cell wall
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a tough, rigid structure outside of the cell membrance in plant cells
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cnidarian
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invertebrate water animal which has tentacles
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omnivores
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an animal whose food source consists of both plants and animals
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herbivores
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an animal which feeds only on grass and other plants
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vertebrate
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an animal with a backbone
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carnivore
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an animal that eats other animals
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polyp
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a cnidarian with a cylindrical body
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medusa
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a cnidarian with a transparent, umbrella-shaped body
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mimicry
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plants and animals which closely resemble another species as a form of protection
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parasite
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an organism that lives and feeds on another living organism for competion of its life cycle, and which is typically detrimental to the host
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symmetry
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the characteristic of being the same on both sides of a central dividing line
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sea anemone
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colorful sea animal of the cnidarian family which attaches to rock or other nonliving material
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sponge
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a sessile marine organism with a porous, fiberous skeleton
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athropods
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invertebrate animals that have jointed bodies and jointed limbs
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metamorphosis
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the change which takes place as an animal developes into an adult (tadpole to frog, caterpillar to butterfly)
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radula
answer
a band of tissue containing rows of small teeth in the mouths of some mollusks
question
echinoderms
answer
a marine invertebrate animal with tube feet and five-part radially symmetrical bodies
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molting
answer
an athropod's process of shedding an old exoskeleton
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setae
answer
rigid, bristle-like structures in worms that assist in movement
question
mollusk
answer
an invertebrate with a soft, unsegmented body; usually has a shell
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spiracles
answer
small opening in an insect along the side of the thorax or abdomen controlling the flow of air into and out of the body
question
appendage
answer
a body part that sticks out from the main part of the body
question
bivalve
answer
a mollusk with a hinged shell; oysters, mussels, and clams are examples
question
gizzard
answer
structure in invertebrates and fish where digestion occurs
question
crop
answer
a pouch in athe digestive tract of an insect or earthworm
question
exoskeleton
answer
gard, protective outer covering of an organism
question
reptile
answer
a cold-blooded animal which breathes air and lays eggs
question
amphibian
answer
a cold-blooded animal that spends time on land but breeds in water
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endoskeleton
answer
the internal skeleton of an animal
question
cartilage
answer
the tough, elastic tissue in the body
question
mammal
answer
warm-blooded animals who are equipped to nurse their young
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endotherm
answer
warm-blooded animal which can maintain its body temperature regardless of temperature changes in its environment
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ectotherm
answer
cold-blooded animal which maintains its body temperature by taking in heat from its environment
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venom
answer
a poisonous fluid produced and injected by an animal to protect itself or to subdue its prey
question
hibernation
answer
a dormant, sleeplike state accompanied by a very low body temperature and metabolic rate; certain animals fall into this during winter
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notochord
answer
a rod of cells that supports the body of a chordate
question
scales
answer
bony plates on fish, some reptiles, and mammals
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larva
answer
immature or early form of an insect, amphibian, or fish
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down
answer
a covering of soft hair or fluffy feathers
question
manatee
answer
a very large, plant-eating mammal that lives in warm coastal waters
question
monotremes
answer
an egg-laying mammal
question
marsupial
answer
a mammal with a pouch used to carry their immature young
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gestation
answer
the period of time when the embryo develops in the uterus
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keratin
answer
fibrous protein found in hair, nails, feathers, and hooves
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placenta
answer
vascular organ that supplies food and oxygen to the fetus inside the uterus of a pregnant mammal
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preen
answer
the process birds go through to clean and to rub oil over their feathers
question
circulatory
answer
the body's blood-pumping system
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contour
answer
contour feathers are the tail and wing feathers, the strong and stiff ones adapted for aerodynamics and speed
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cyclic
answer
occuring repeatedly during specific intervals of time
question
social
answer
behavior of a species living together in a group
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imprinting
answer
the early social attachment of animals that results in strong behavioral patterns specific to its own species
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migration
answer
a cyclical behavior in which a group of animals move together from one region to another
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pheromone
answer
a scent which is secreted by an animal, influencing behavior and development of other members of the same species
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instinctive
answer
behavior in which an animal reacts out of a strong natural impulse
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innate
answer
qualities which are present at birth
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insight
answer
a learned behavior which allows animals to use past experiences to solve new problems
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aggression
answer
a territorial behavior exhibited by the threatening actions of one animal to another
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bioluminescence
answer
the light given off by some organisms such as fireflies
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territorial
answer
animal tendency to protect an area from intruders of the same species, especially other males
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tendons
answer
a connective tissue that attaches a muscle to a bone or other body part
question
dermis
answer
the layer of skin under the epidermis which contains blood, lymph vessels, sweat glands, and nerve endings
question
skeletal system
answer
the system of bones supporting the soft tissue and protecting the internal organs of the body
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muscle
answer
an elastic tissue that functions to produce movement of body parts and body fluids
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periosteum
answer
the connective tissue surrounding all bones of the body except those at the joints
question
ligaments
answer
the bands of tough tissue that connect bones or cartilage at a joint or that support an organ or muscle
question
melanin
answer
a dark brown or black pigment found in skin, hair, eyes, fur, or feathers of people, animals, and plants
question
joint
answer
the point at which two or more bones in the body come together
question
bruise
answer
a discoloration of the skin caused by injury to blood vessels
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voluntary
answer
a controlled response
question
involuntary
answer
an uncontrolled response
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nutrient
answer
a substance that provides nourishment for the body
question
digestion
answer
the breaking down of food in the body so that it can be used or excreted
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salivary glands
answer
glands that producce and release digestive juices (saliva) in the mouth
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carbohydrate
answer
food energy source for humans and animals such as sugar and starch
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villus
answer
part of the small intestine
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esophagus
answer
the pathway in the throat through which food moves between the throat and the stomach
question
enzyme
answer
a protein controlling biochemical reactions
question
chyme
answer
a mass of partially digested food and gastric secretions passed from the stomach to the small intestine
question
protein
answer
a food source rich in amino acids
question
peristalsis
answer
involuntary muscle contractions that transport food and waste through a tube-shaped organ such as the intestine
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calorie
answer
a unit of energy equal to the heat needed to raise the temperature of one kg of pure water by one degree Calcius
question
atrium
answer
one of the upper chambers of the heart
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ventricles
answer
the lower chambers of the heart
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lymph
answer
fluid containing the white blood cells
question
pulmonary circulation
answer
the flow of blood from the heart to the lungs and back to the heart
question
plasma
answer
the clear, yellow fluid part of blood
question
tricuspid
answer
a heart valve with three flaps; prevents blood from flowing back into the right atrium when the right ventricle contracts
question
mitral
answer
a heart valve that lies between the left atrium and left ventricle; prevents blood from flowing back into the left atrium when the left ventricle contracts
question
lymphatic
answer
a vessel that transports or contains lymph
question
platelets
answer
colorless cells whose main function is to control bleeding
question
cardiovascular system
answer
the system made up of heart, blood vessels, and blood
question
microscopic
answer
unable to be seen without the aid of a microscope
question
capillaries
answer
the thin blood vessels that connect small arteries with small veins
question
systemic circulation
answer
the circulation of the blood throughout the body
question
hypertension
answer
elevated blood pressure
question
coronary
answer
the arteries and veins that supply blood to and from the muscle tissue of the heart
question
diffusion
answer
the process of distributing nutrients to the cells
question
aorta
answer
the main artery leaving the heart
question
vena cava
answer
main veins leading into the heart
question
blood vessels
answer
tubes that carry blood throughout the body
question
bronchi
answer
the two main air passages leading from the trachea which allow air to move in and out of the lungs
question
urine
answer
the liquid waste product of vertebrates
question
cellular respiration
answer
the process by which glucose is converted into energy
question
alveoli
answer
air sacs in the lung
question
respiratory system
answer
the system of organs that process air in the body, including the nose, throat and lungs
question
asthma
answer
respiratory disease characterized by wheezing and shortness of breath
question
kidneys
answer
the pair of organs responsible for filtering waste liquid in the body
question
trachea
answer
the airway that leads from the larynx to the lungs
question
diaphragm
answer
muscular wall below the rib cage which expands the chest for breathing
question
emphysema
answer
lung disease in which the air sacs are dilated resulting in breathing impairment
question
excretory system
answer
the organs that elimate waste from the body
question
nephrons
answer
small tubes in the kidneys
question
urethra
answer
the tube that carries urine from the bladder to the outside of the body
question
glucose
answer
a simple sugar which is the main source of energy for the body
question
lobe
answer
a rounded part of an organ, as in the lungs, brain, or liver
question
dialysis
answer
the mechanical filtering of waste products from the blood of a patient whose kidneys are not working properly
question
nervous system
answer
the body system that receives stimuli, decides on their importance, and sends nerve impulses to the organs of action; consists of the central nervous system ( brain and spinal cord) and the peripheral nervous system (all nerves outside of the brain and spinal cord)
question
neurons
answer
cells that transmit nerve impulses and are the basic units of the nervous system
question
axons
answer
the extensions of a nerve cell that transmit impulses outward or away from the cell body
question
dendrites
answer
extensions of a nerve cell that receive electrical signals
question
central nervous system
answer
the control network for the human body; is composed of the brain and spinal cord; one of the two major divisions of the nervous system
question
cerebellum
answer
part of the brain which controls and coordinates muscular activity and balance
question
retina
answer
a light-sensitive membrane in the back of the eye which receives an image from the lens and sends it to the brain
question
hammer
answer
tiny bone located in the inner ear
question
brain stem
answer
the part of the brain closest to the spinal cord that controls involuntary functions like breathing and heart rate
question
saliva
answer
liquid secreted into the mouth by the salivary glands which moistens food and begins the breakdown of starches
question
peripheral nervous system
answer
the nerves in the body that lie outside of the brain and spinal cord
question
concave
answer
curved inward
question
convex
answer
curved outward
question
cranial
answer
relating to the skull
question
somatic system
answer
system that controls all voluntary systems within the body with the exception of reflex arcs
question
autonomic system
answer
the part of the nervous system that controls involuntary activity such as the action of the heart, lungs, and intestines
question
olfactory cells
answer
relating to the sense of smell
question
rods
answer
cells in the retina used to detect shape and movement
question
homeostasis
answer
the natural regulatory mechanism of the body
question
taste buds
answer
receptors primarily on the tongue that enable us to detect sweet, salty, sour and bitter
question
endocrine system
answer
the system of glands in the human body which is responsible for producing hormones
question
fraternal
answer
relating to twins that developed from two seperate ova, rather than a single ovum
question
identical
answer
relating to twins that developed from a single ovum in a single placental sac; these twins closely resemble one another
question
amniotic sac
answer
the sac which holds the baby in the uterus; contains the baby, placenta and amniotic fluid
question
reproduction
answer
the production of offspring
question
hormones
answer
produced by the endocrine glands, these substances act as messengers to cells and organs in the body
question
puberty
answer
the state of physical development when sexual reproduction first becomes possible
question
fetus
answer
in mammals, a stage of development in which all organs have formed, from the eighth week after conception until the moment of birth
question
embryo
answer
in mammals, the stage of development from conception to eight weeks
question
thyroid gland
answer
the gland which helps regulate growth and metabolism
question
thymus gland
answer
a gland involved in the development of cells of the immune system
question
pituitary gland
answer
the main gland of the endocrine system
question
pineal gland
answer
small gland responsible for production of melatonin
question
uterus
answer
the organ which holds and nourishes the embryo during development
question
immune system
answer
system that works to seek and kill invaders of the body
question
menstrual cycle
answer
monthly cycle of female hormonal changes from the beginning of one menstrual period to the beginning of the next
question
ovulation
answer
the ripening and release of an egg or eggs from the ovary for possible fertilization
question
scrotum
answer
the pouch of skin and muscle containing the testicles
question
umbilical cord
answer
the cord that carries blood, oxygen, and nutrients from the plancenta to the baby during pregnancy
question
gland
answer
an organ that produces and releases one or more substances for use in the body
question
tonsils
answer
organs at the back of the throat that help the body figh toff viral and bacterial infections
question
antibody
answer
a protein that combines with an antigen and counteracts in its effects
question
allergens
answer
any substance that triggers an allergic reaction
question
immunity
answer
a body's ability to resist a specific disease
question
communicable
answer
easily transmitted from one person to another
question
vector
answer
carrier of an infectious agent; capable of transmitting infection from one host to another
question
antigens
answer
a substance that simulates the production of antibodies
question
chronic illness
answer
a recurring ilness
question
asbestos
answer
a mineral fiber used in the past for fireproofing and insulation; banned by EPA because it was found to cause caner when inhaled
question
the molecules
answer
the smallest parts of matter
question
pathogens
answer
a disease-producing organism
question
chemotherapy
answer
the use of chemical agents to treat cancer and other diseases
question
abiotic
answer
nonliving
question
biotic
answer
living
question
chemosynthesis
answer
the process by which some bacteria use chemicals to provide the energy they need for life
question
evaporation
answer
the process in which a liquid is changed to a vapor without its temperature reaching the boiling point
question
condensation
answer
water droplets that form on cold surface when warmer air comes in contact with it
question
transpiration
answer
the loss of water vapor from a plant's surface
question
precipitaion
answer
the formation of rain, snow, or hail from moisture in the air
question
ecosystems
answer
a community of different species interacting with one another and their environment
question
biomes
answer
an ecological community of organisms and environments
question
taiga
answer
sub-arctic forests located south of a tundra
question
tundra
answer
treeless plain between the ice cap and the timber line that had permanently frozen subsoil
question
wetlands
answer
an area of land, marsh or swamp, where the soil near the surface is covered with water
question
acid rain
answer
rain that has becom acidic from mixing with industrial pollutants in the atmosphere (like oxidated sulphur and nitrogen)
question
recycling
answer
the processing of waste for reuse
question
solar energy
answer
using the sun as an energy source
question
nuclear energy
answer
energy released by nuclear fission or fusion
question
nitrogen cycle
answer
nitrogen circulation between air and plants
question
smog
answer
a mixture of fog and smoke which creates a type of pollution
question
energy pyramid
answer
a pyramid diagram showing the loss of useful energy at each steop in a food chain
question
covalent bonds
answer
chemical bonding where some atoms share electrons to hold a molecule together
question
molecule
answer
term used to describe a group of atoms connected by covalent bonds
question
compound
answer
substance made up of more than one element
question
states of matter
answer
solids, gases, liquids, and plasmas
question
element
answer
substance composed of only one type of atom
question
crystals
answer
solids in which the atoms are arranged in a repeating, orderly pattern
question
streak
answer
property revealed by rubbing a mineral on an unglazed seramic tile to determine the color of the mineral in powdered form
question
luster
answer
term used to describe how a mineral reflects light
question
halite
answer
salt or sodium cholride; colorless or white mineral occuring as cubic crystals
question
mineral properties
answer
luster, streak, hardness, and fracture
question
hardness
answer
strength of the structure of the mineral compared to the strength of its chemical bonds, tested through scratching
question
fracture
answer
one way that a mineral can break; smoothly curved, irregular, jagged, or splintery
question
silicon
answer
nonmetallic element found only as a compound with other elements in nature
question
clevage
answer
another way that a mineral can break; found mainly in crystalline minerals like diamonds which can break in straight planes when struck
question
sediment
answer
particles of eroded rock or other plant or animal matter that are transported and deposited by water, wind, ice, or gravity
question
foliated rock
answer
rock that has a layered appearance, formed or composed of separable layers
question
igneous rock
answer
type of rock formed by intense heat or from solidification of molten magma
question
sedimentary
answer
type of rock formed from eroded material or sediment
question
metamorphic
answer
type of rock characterized by a change in physical form, appearance, or character
question
lava
answer
type of molten rock that comes from a volcano; magma that has reached the surface of earth
question
intrusive rock
answer
type of rock that is formed by being forced into the holes, cracks, or layers of preexisting rocks while in a molten state
question
obsidian
answer
volcanic glass that is formed by rapid cooling of lava and usually black in color; used by early civilizations to make tools and special objects
question
magma
answer
molten rock that is in a liquid state under the earth's crust; forms igneous rock when cooled at earth's surface
question
coal
answer
black or dark brown sedimentary rock used as a fuel; formed by the decompostition of plant material
question
latitude
answer
how far north or south of the equarot a point id on earth's surface
question
prime meridian
answer
imaginary line that runs from north to south though Greenwich, England; at 0 degrees longitude, all other longitudes are figured from this one
question
longitude
answer
the east or west distance between a point on the earth and the prime meridian
question
map projection
answer
a flat map that shows our three-dimensional eath
question
cartography
answer
the study and creation of maps
question
elevation
answer
height of an area, object, or land form on the earth's surface above sea level
question
topographic map
answer
map showing the physical features and elevation of an area
question
coastal plain
answer
flat. low-lying land next to a sea coast
question
plateau
answer
an elevated, mostly level or flat area of land
question
volcano
answer
vent or opening in earth's surface through which molten magma (lava), ash, and gases are released
question
fault-black
answer
mountain formed by the uplift of land between faults or the lowering of land outside of the faults
question
equator
answer
imaginary circle around the surface of earth halfway between the North and South Poles
question
horizons
answer
layers of soil visible in a vertical cross section
question
oxidation
answer
chemical reaction where oxygen is combined with another element or compound to yield a different compund (example: iron + oxygen + rust)
question
carbonation
answer
process where dissolved carbon dioxide in rainwater creates carbonic acid and reacts with minerals in a rock to break it down
question
hydrolysis
answer
process where hydrogen in rainwater reacts with minerals in a rock to break it down
question
abraision
answer
form of weathering that occurs when sand or other small particles transported by air collide with surfaces and break them down
question
chemical weathering
answer
process in which rocks decompose or disintergrate by chemical processes such as oxidation, carbonation, or hydrolysis
question
mechanical weathering
answer
process where rocks are broken down into smaller pieces and their edges are rounded by abrasion, gravity, and freezing water
question
erosion
answer
the wearing away of land surface (soil) or rocks by wind, water, or ice
question
leaching
answer
process by which soil nutrients are carried away by water or washed deeper into the soil
question
limestone
answer
sedimentary rock formed mostly from the calcium carbonate remains of marine animals such as shells; used to make cement and lime
question
terrace farming
answer
transformation of a cary steep slope into usable farmland by creating a series of level steps or terraces; these terraces or steps retain water and keep plants and seeds from washing downhill
question
glacier
answer
very large mass of ice and snow that moves slowly downhill because of its own weight; is an agent of erosion; formed in areas where sonw falls faster than it melts
question
mass movement
answer
downhill movement of earth materials due to gravity
question
creep
answer
form of erosion caused by gravity where uphill particles fall downhill very slowly; form of mass movement
question
mudflow
answer
rapid downward movement of wet soil; form of mass movement
question
slump
answer
mass movement or lanslide where moving earth moves downward in a block or multiple blocks and can create a small upslope in the process
question
subsidence
answer
downward movement of earth
question
beach erosion
answer
the wearing away of a beach by tides, currents, and waves
question
wind erosion
answer
wind action primarily known for smoothing and rounding landscapes as sand and dust carried by wind wear away rocks and land surface
question
loess
answer
windblown, dusty, chalky soil or silt; usually yellowish-brown
question
striatioin
answer
scratch or groove on a rock formed by a glacier or stream
question
deposition
answer
opposite of erosion; also known as sedimentation; sediment which eroded from another location, was transported by wind,water, or ice, and deposited
question
deflation
answer
wind erosion where sand, clay, and silt particles are removed from the land's surface
question
eskers
answer
long, winding ridges of sand and gravel deposited by streams that flows in or under glaciers
question
glacial till
answer
rocks and material left behind by a glacier
question
moraine
answer
new landform crated by the accumulation of rocks, soil, and other debris carried and deposited by a glacier (glacial till)
question
cirque
answer
bowl-shaped valley with steep walls on a mountain eroded by a glacier
question
crust
answer
very thin outer layer of the earth (25 miles under the continents, two to three miles under the oceans); broken into pieces called plates
question
mantle
answer
thickest layer of the earth (about 1800 miles thick); made of hot, dense rock that flows and moves due to temperature differences in the mantle
question
outer core
answer
1800 miles beneath the crust; composed of nickel and iron in a liquid state due to high temperatures
question
inner core
answer
very hot (4,000 to 9,000 degrees F) solid center of the earth composed mainly of nickel and iron; solid due to extremely high pressure; about 3200 miles below the earth's surface and about 800 miles thick.
question
epicenter
answer
point on the earth's surface directly above the source of an earthquake
question
seismograph
answer
device that detects, measures, and records earthquake vibrations
question
seismologist
answer
scientist who measures and studies earthquakes
question
Richter Scale
answer
collection of mathematical formulas that measure the strength of an earthquake; developed by Charles Richter in 1935
question
tsunami
answer
huge ocean waves generated after an earthquake at sea where there is a sudden drop or rise of a large section of the ocean floor
question
surface wave
answer
vibration from an earthquake that travels along the surface of the earth and can topple buildings during an earthquake
question
body waves
answer
vibration from an earthquake that travels deep within the earth; two types are primary and secondary waves
question
primary wave
answer
type of body wave that compresses and expands rock as it travels through the earth
question
secondary wave
answer
type of body wave that shakes and twists the earth sideways as it travels; moves at about half the speed of the primary wave
question
magnitude
answer
measure of the size or energy of an earthquake
question
elasticity
answer
property that alllows a material to bend and change shape
question
seismic wave
answer
vibration that travels through the earth, usually due to an earthquake
question
liquefaction
answer
process of changing a solid or gas into a liquid
question
normal fault
answer
break in the earth's crust where a block of rocks shifts downwards
question
strike-flip fault
answer
break in the earth's crust where rocks on either side of the fault split and slide past each other
question
plate boundaries
answer
edges of the plates that make up the broken surface of the earth
question
volcanic eruption
answer
violent discharge of steam, lava, and ash from a volcano; usually occurs on or near the continental plate boundaries; produces ash, granite and basalt
question
sill
answer
flat mass of igneous rock between two layers of older, existing sedimentary rock; mass is usually horizontal
question
volcanic neck
answer
massive, crudely cylindrical pillar of rock that was the inside (neck) of a volcano which filled with magma and hardened many years ago; is now exposed due to surface area erosion around the projection
question
batholith
answer
huge mass of igneous rock (greater than 40 square miles) with no known bottom; believed to have solidified deep within the earth
question
caldera
answer
large bowl-shaped volcanic depression formed at the top of a volcano when the vent collapsed; sometimes filled with water
question
Krakatoa
answer
volcano on the Indonesian island of Rakata; has erupted many times throughout history with disastrous consequences
question
Hawaiian Islands
answer
islands in the Pacific Ocean; formed in a nearly straight line because the Pacific plate moved very slowly over a hot spot in the Earth's mantle layer
question
La Soufriere
answer
volcano on the Caribbean island of Montserrat known for its high levels of silica, a substance potentially hazardous to humans
question
Kilauea
answer
youngest volcano on the Big Island of Hawaii; possibly the world's most active volcano with continuous eruptive activity since 1983
question
tephra
answer
bits of solidified lava that fall from the air and can be as small as ash or as large as rocks
question
Mt. St. Helens
answer
active volcano in Washington state that had a massive eruption in 1980 which produced tremendous amounts of ash
question
composite volcanos
answer
tall, symmetrical, steep-sided volcanoes, also known as stratovolcanoes
question
shield volcano
answer
flat, broad volcano such as Mauna Loa in Hawaii
question
Paricutin Volcano
answer
Mexican volcano that appeared first as a crack in a cornfield then eventually produced 10 square miles of lava and buried most of Paracutin and nearby San Juan
question
cinder cone
answer
volcanic cone that forms above ground around a vent; is made of cinders (loose volcanic fragments) and bombs (ashes and blobs of congealed lava)
question
Pangaea
answer
name given to ancient super-continent consisting of all of earth's masses; theory was proposed by German meteorologist Alfred Wegener in 1915
question
continental drift
answer
the gradual movement and formation of continents; idea supported by fossil evidence of same unique plants/animals on multiple continents
question
plate tectonics
answer
theory that the earth's surface is broken into plates the size and position of which change over time; this theory supports the continental drift theory
question
subduction zone
answer
an area on earth where two tectonic plates meet; one plate slides underneath the other, moves down into the mantle and melts
question
fossils
answer
traces or remains of animals or plants from long ago
question
lithosphere
answer
crust and the uppermost part of the earth's mantle
question
asthenosphere
answer
lower layer of the mantle that flows and moves the plates of the earth
question
ropy lava
answer
long trails of lava that form spirals
question
magnetic reversals
answer
changes in earth's magnetism (evidenced in rods) due to slow movements in earth's liquid outer core; this phenomenon supports the idea that the sea floor is changing and spreading
question
convection
answer
material movement in gases and liquids due to density or concentration differences which are often a result of heat
question
fossil formation
answer
accomplished by permineralization, carbon film, or molds
question
permineralization
answer
the process in which minerals are deposited into a bony fossil
question
carbon film
answer
a type of fossil formation normally involving plants where a plant's oils leach out and only a black carbon film remains
question
mold
answer
a type of fossil formation where an organism is buried in mud, clay, or another material which hardens, the organism decays, and an imprint of the organism is left in the hardened material
question
rock record
answer
ancient history recorded in rock layers
question
unconfomity
answer
a boundary seperating two or more rocks of markedly different ages, marking a gap in the geologic period
question
index fossils
answer
fossils that existed during limited periods of time; used to determine the age of the rocks in which they are preserved
question
carbon dating
answer
dating method that uses carbon-14 to determine the age of the materials
question
uniformitarianism
answer
principle which states that sediments formed in ancient sedimentary rocks were deposited in the same way sediments are deposited today
question
superposition
answer
principle stating that in undisturbed situations, the oldest layers of rock are on the bottom
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fossilized footprints
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evidence of early human ancestors found by Mary Leakey in Africa
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trilobite
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extinct marine organism that lived in earth's oceans for more than 200 million years; thought to be ancestor of today's joint-footed organisms; crabs, centipedes, spiders, etc.
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eon
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longest block of time in geology
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era
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period of time that is a sundivisioin of an eon
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period
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divisioin of an era into smaller time frames
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epoch
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division of a period into smaller time blocks
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Precambrian Eon
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time period from the formation of earth up until about 600 million years ago
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Phanerozoic Eon
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time period from 600 million years ago until now
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Paleozoic Era
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time period from about 600 million years ago to 245 million years ago when the super continent pangaea is thought to have been formed and the first fish, land plants, amphibians, and reptiles firs appeared; first era of the Phanerozoic Eon
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Mesozoic Era
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time period from between 245 million years ago to 5 million years ago when dinosaurs, the first birds, and mammals appeared; period ended by mass extinction; second era of the Phanerozoic Eon
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Cenozoic Era
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time period that spans from 65 million years ago until now; the Age of Mammals; the third era of the Phanerozoic Eon
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cyanobacteria
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organism from the Precambrian Eon that contained chlorophyll and contributed oxygen to earth's atmosphere through photosynthesis; created our oldest fossils
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Charles Darwin
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English scientist who wrote the book The Origin of Species (1859) and achieved lastingn fame for his theory of evolution
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evolution
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process of change over time
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Tyrannosaurus
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mobile, meat-eating dinosaur from the Jurassic period
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species
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group of organisms that normally breed only among themselves
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troposphere
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lowest layer of earth's atmosphere; extends from earth's surface up to about 8 miles high
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stratosphere
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atmospheric layer above the troposphere; 9 to 31 miles above the earth
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mesosphere
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layer above the stratosphere; about 31 to 50 miles above the earth
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thermosphere
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outermost layer of earth's atmosphere where gas molecules split apart into ions
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ionosphere
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lower part of the thermosphere; reflects radio waves
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sea breeze
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a breeze that forms when warmer air over the land rises and cooler costal air rushes in to replace it
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atmospheric pressure
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force exerted by the weight of the air; as altitude (height above earth's surface) increases, atmospheric pressure decreases because air is less dense, and vice versa (altitude decreases, pressure increases)
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water cycle
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continuous process of moving water from the earth to the atmosphere and back again; evaporation, condesation, precipitation
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ozone layer
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exists in the stratosphere; atmospheric layer of oxygen that exists as ozone and absorbs harmful ultraviolet radiation
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jet stream
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fast moving river of air that flows from east to west over North America and directs our weather systems
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trade winds
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strong tropical winds blowing toward low pressure regioins at the equator; the blow from east to west in the Northern Hemisphere
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prevailing westerlies
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winds in the middle latitudes that generally blow opposite the trade winds; primarily responsible for blowing weather patterns across the United States
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doldrums
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areas near the equator where the is little or no wind
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conduction
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transfer of heat through materials
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convection
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heat transfer by circulation through a gas or liquid
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radiation
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energy or heat carried in waves or rays
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coriolis effect
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curving motion of wind or water caused by the earth's rotation
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chlorofluorocarbons
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also know as CFC's; chemical substances once used in refridgeratiors and air conditioners that destroy the ozone layer when they break down
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weather
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state of the atmosphere at a specific time and place
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humidity
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water vapor in the air
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tornado
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severe storm with a violent, rotating column of air that can have wind speeds greater than 150 miles per hour
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tropical storm
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organized thunderstorm over tropical waters with winds from 39 to 74 miles per hour; storm winds spin due to earth's rotation
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hurricane
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severe tropical storm with sustained winds of 75 miles per hour or more; starts over the ocean and is the most powerful type of storm on earth
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cirrus clouds
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high, thin, featherlike clouds of ice crystals
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altocumulus clouds
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white or gray medium altitude clouds that usually occur in layers or patches of wavy rounded masses or rolls
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stratus clouds
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low, gray, uniform cloud layer that usually covers the sky
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cumulonimbus clouds
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thunderstorm cloud that is extremely dense and tall, associated with lightning, thunder, hail and sometimes tornadoes
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dew point
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specific temperature when water vapor in the air condenses
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precipitation
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water that falls to earth as rain, snow, hail or sleet
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climate
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average weather pattern of a region that occurs over many years and is influenced by latitude, ocean currents, mountains, and large bodies of water
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deforestation
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destruction of forests
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greenhouse effect
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warming of the earth's atmosphere due primarily to heat trapped by gases such as carbon dioxide, methane and water vapor; deforestation adds to this problem because it removes trees that would have removed carbon dioxide from the air and reduced the greenhouse effect
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El Nino
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weather pattern usually occurring every 3 to 5 years when abnormally warm surface waters occur in the Pacific Ocean near Peru
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Gulf Stream
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warm ocean current that flows from the Gulf of Mexico along the east coast of the U.S. and northeast across the Atlantic Ocean
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desalinization
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process of removing salt from water
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upwelling
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upward motion of cold, dense, nutrient-rich water toward the surface
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continental shelf
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shallow bottom just offshore of most continents between the beach (edge of the water) and a sharp underwater drop-off where the bottom plunges steeply
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wavelength
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distance from crest to crest of a wave
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current
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stream of water that moves horizontally in the ocean
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ocean pollution
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major causes include: 1) toxic (poisonous) trash and chemicals that get into our food chain, 2) oil, primarily occurring as runoff from the land, and 3) dangerous debris like plastics that can entangle animals and harm marine life when eaten
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tides
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the daily, regular rise and fall of the ocean waters due to the moon's gravitational pull on the earth
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benthic organisms
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bottom-dwellers in a body of water
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plankton
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minute animals and plants that are free-floating and unable to swim against currents
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nekton
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water animals that are active swimmers and capable of swimming against a current; not plankton
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estuary
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wide part of a river where it joins the sea; fresh and salt water mix here
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food chain
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a hierarchy of living things (animals and plants) where each level is dependent on the next for its nourishment
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ocean waves
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as water molecules in a wave move up and down in a circular pattern, the energy of the wave moves toward the shore; friction with the bottom slows the wave as it nears the shore
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sting ray
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fish with a flattened body and a long, narrow whip-like tail with a venomous stinger; can inflict severe wounds
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jellyfish
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free-swimming sea animal with a bell-shaped, jelly-like body and stinging tenticles
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pH
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a measure of acidity or alkalinity
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acidity
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acidity of a water sample is determined by titrating it with a strong base (eg, NaOH) to a defined pH; pH less than 7
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alkalinity
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a pH of more than 7; the solution is considered base or alkali
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neutral
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a pH of about 7
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detergent
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a man-made chemical cleanser
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sewage
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filthy waste from household or industrial sources that is carried away in drains
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scrubber
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a filter or purifier that removes impurities (particles and contaminants) from the air
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pollution
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something that contaminates our environment; can even be clean water that is too warm if it is drained into cool water and changes the habitat of animals there
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acid rain
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rain drops that have a pH of less than 5.6 because they have mixed with pollutants such as sulfur or nitrogen; can affect animals such as snails and birds by removing calcium from their habitat (calcium is needed to make snail shells and bird eggs)
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particulates
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tiny, solid particles such as dust, ash, soot, or pollen that are released into and move around in the air
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smog
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polluted or dirty fog caused mainly by cars
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photochemical smog
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brown haze that contains ozone and blankets a city when car and truck exhaust react with sunlight
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fertilizer
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natural or man-made plant nutrient added to enhance plant growth; can cause problems (such as excessive algae growth) in streams or ponds if too much fertilizer runs off of yards or farms
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Clean Water Act of 1977
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Federal government regulation to restore and maintain the health and integrity of our nation's waters; requires communities to treat sewage before releasing it into a river
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sulfur dioxide
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air pollutant formed when fuel containing sulfur is burned; a colorless, irritating gas that contributes to formation of acid rain
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inversion
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thermal inversion: when a layer of warm air lies over cooler air near the ground, trapping pollutants
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electrostatic separator
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a machine used to separate substances by using electrical charges
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Cuyahoga River
answer
river located in northeast Ohio; when a layer of oil and debris (pollution) on its surface caught fire in 1969, our nation pain attention; concern over pollution causing the fire led to the Clean Water Act of 1977
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carrying capacity
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maximum population that the environment can support without negative effects
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sanitary landfill
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environmentally safe method of waste disposal where a landfill has a waterproof liner and is covered daily to keep harmful materials from entering the air and soil
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recycle
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to use a resource again
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20th century
answer
1900 through 1999
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world population
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total number of humans alive on the planet earth at a given time; the last 70 years of the 20th century saw the biggest increase in the world's population in human history
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hazardous waste
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solid, liquid, or gaseous material that is discarded and can harm people, animals or the environment; requires special disposal
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phytoremediation
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use of plants to clean up polluted sites, usually by absorbing contaminants through their roots
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compost
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way to recycle organic matter; by using natural processes, organic matter decomposes and becomes nutrient-rich soil builder
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pollutant
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any substance that harms the environment when it mixes with soil, water or air
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per capita
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per person
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telescope
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an astronomical tool used to see distant objects such as those in space; first invented by Galileo in 1610
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Sputnik
answer
first artificial satellite; put into Earth's orbit in 1957 by the Soviets; led to creation of NASA and the race to the moon
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Hubble Space Telescope
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a telescope orbiting the Earth; its position outside the earth's atmosphere allows it to take sharp optical images of very faint objects
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satellite
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object that revolves around a planet
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moon
answer
natural satellite of Earth
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orbit
answer
the path that an object makes around another object
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Apollo
answer
U.S. space program that included 6 piloted moon landings between 1969 and 1972
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Saturn rocket
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rockets developed for the Apollo program to launch heavy payloads to Earth's orbit and beyond
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Voyager space probes
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two unmanned space probes: Voyager I and Voyager 2; launched in 1977; sent to study Jupiter and Saturn, went on to Uranus and Neptune, and then into the outer solar system
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Spirit & Opportunity
answer
twin robotic exploration rovers developed by NASA and sent to Mars in January 2003; these computers on wheels make observations and report them to NASA
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Yuri Gagarin
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Soviet cosmonaut (astronaut) who was the first human in space (1961)
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John Glenn
answer
first U.S. man to orbit Earth (1962)
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Neil Armstrong
answer
first man to walk on the moon (1969); an American
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electromagnetic spectrum
answer
entire range of electromagnetic radiation including: radio, microwave, infrared, visible light, ultraviolet, x-ray, and gamma ray radiation
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space shuttle
answer
reusable spacecraft that can carry a payload into orbit then return to Earth with its crew
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space station
answer
permanent laboratory and exploration platform in space
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solar eclipse
answer
the name of the event when the moon comes directly in between Earth and the sun and interrupts the light from the sun
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elliptical
answer
having an oval shape, rounded like an egg
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meteor
answer
a piece of rock or metal that enters Earth's atmosphere but usually burns up before reaching Earth's surface
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Gibbous moon
answer
descriptive name for the moon when it is between a full moon and a half moon (more than half of the moon's surface is visible)
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equinox
answer
either of two days, usually March 21st or September 23rd, when daylight and darkness are about equal because the sun is directly over the Earth's equator
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axis
answer
an imaginary straight line about which Earth rotates
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solstice
answer
one of two times during the year when the sun reaches its greatest distance from the equator during Earth's orbit, yielding the longest and shortest days of the year
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SOHO mission
answer
joint project between the European Space Agency (ESA) and NASA (US space agency) to investigate the sun
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penumbra
answer
term used to describe the partial shadow that occurs during a lunar eclipse
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North Pole
answer
region of Earth that is a magnetic field because of Earth's rotation; magnetism causes a compass to point north
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asteroids
answer
chunks of rock, pieces of planets, or small planets that primarily orbit the sun in an "asteroid belt" between Mars and Jupiter
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Johannes Kepler
answer
German astronomer best known for his laws of planetary motion
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Mercury
answer
planet nearest the sun; smallest of the inner planets with no atmosphere and no moons
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Venus
answer
2nd planet from the sun; its atmosphere of mostly carbon dioxide traps heat from the surface, producing very high temperatures that lead to the Greenhouse effect on that planet
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Earth
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3rd planet from the sun; the planet we live on
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Mars
answer
4th planet from the sun, appears red due to iron oxide (rust) on its soil
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Jupiter
answer
5th planet from the sun, largest in our solar system with a Great Red Spot; has faint dust rings (that Voyager found) and many moons that include Europa, Ganymede, Callisto and Lo; Lo has active volcanoes
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Saturn
answer
6th planet from the sun with large rings made mainly of ice and rock
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Uranus
answer
7th planet from the sun, unusual because its axis is parallel to the plane of its orbit, not perpendicular like other planets
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Neptune
answer
8th planet from the sun; methane gives Neptune its blue cloud color
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Pluto
answer
9th planet from the sun; recently reclassified as a dwarf planet; Pluto is unusual in its orbit, some parts of Pluto's orbit are inside of Neptune's
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planet
answer
a body in orbit around the sun
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inner planets
answer
the small, rocky planets that orbit closest to the sun including Mercury, Venus, Earth, and Mars
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outer planets
answer
planets that orbit far from the sun including Jupiter, Saturn, Uranus, Neptune and Pluto
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light year
answer
the distance traveled by a ray of light in one year
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nebula
answer
a cloud of gas and/or dust in space
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Sun
answer
medium size star that is at the center of our solar system; innermost layer is the core, then the photosphere, the chromosphere, and the corona
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sunspot
answer
cooler dark spots on the photosphere of the sun; created when magnetic fields stop the circulation of gases
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solar prominence
answer
a large bright feature in the solar corona also influenced by magnetic fields
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magnitude
answer
term used to describe the measure of a star's brightness
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absolute magnitude
answer
measurement of the brightness of a star as if it were a set distance away; allows overall brightness of objects to be compared without regard to distance from the earth
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Milky Way
answer
the spiral galaxy to which our sun and solar system belong
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supernova
answer
explosion caused when a massive star dies and collapses; rare, short-lived phenomenon that throws out vast amounts of energy into space; some so bright that they could be seen even in the middle of the day
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fusion
answer
star's energy source (in its core) where fusion of hydrogen to helium occurs
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black hole
answer
a completely collapsed dead star with a massive gravitational field so powerful that not even light can escape it
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white dwarf
answer
a "tiny" collapsed star about the size of a planet near the end of its nuclear fusion period; white and very hot
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neutron star
answer
a dense ball made up almost entirely of neutrons that remains after a supernova has exploded the rest of the star; extremely dense and more massive than our sun
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Big Bang Theory
answer
a theory of universe creation that assumes our universe began about 20 billion years ago with a super-powerful explosion
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