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change of state
a physical change that occurs when matter changes to another state (i.e., liquid, gas, or solid)
a reaction or a change in a substance produced by chemical means that results in producing a different chemical
all the populations of organisms belonging to different species and sharing the same geographical area
the process of changing from a gas (i.e., water vapor) to a liquid (i.e., dew); the act of making more dense or compact
controlled use and/or maintenance of natural resources; various efforts to preserve or protect natural resources efforts to preserve or protect natural resources
a star pattern identified and named as a definite group; usually thought of as forming certain shapes or figures in a specific region of the sky
any organism that feeds or obtains nutrients by breaking down organic matter from dead organisms
concentration of matter of an object; number of individuals in the same species that live in a given area; the mass per unit volume of a substance in a given area
a pyramidal diagram that compares the amount of energy available at each position, or level, in the feeding order
a procedure that is carried out and repeated under controlled conditions in order to discover, demonstrate, or test a hypothesis; includes all components of the scientific method
transfer of energy through various stages as a result of feeding patterns of a series of organisms food web (food cycle) the interconnected feeding relationships in a food chain found in a
food web (food cycle)
the interconnected feeding relationships in a food chain found in a particular place and time
a quality that tends to produce movement or acceleration of a body in the direction of its application; a push or pull
a large collection of stars, gases, and dust that are part of the universe bound together by gravitational forces
one of the fundamental states of matter in which the molecules do not have a fixed volume or shape
a form of energy resulting from the temperature difference between a system and its surroundings
a type of simple machine; a slanted surface that makes it easier to move a mass from a lower point to a higher point
the property of a body, due to its mass, that causes it to resist any change in its motion unless overcome by a force
a procedure that is carried out in order to observe a response caused by a stimulus; not a complete experiment
a type of simple machine; consists of a rigid bar that pivots about a fulcrum, used to transmit and enhance power or motion
having the property of attracting iron and certain other materials by virtue of a surrounding field of force
a type of rock that forms from existing rock because of extreme changes caused by heat, pressure, or chemical environments
a phrase that indicates the fraction of the Moon's disc that is illuminated (as seen from Earth); the eight moon phases (in order)new moon, waxing crescent, first quarter, waxing gibbous, full moon, waning gibbous, last quarter, waning crescent
a structure containing different tissues that are organized to carry out a specific function of the body (e.g., heart, lungs, brain, etc.)
any living plant, animal, or fungus that maintains various vital processes necessary for life
a chemical process by which plants trap light energy to convert carbon dioxide and water into carbohydrates (sugars)
a reaction; a change in matter from one form to another, without forming new substances
any alteration of the natural environment producing a condition harmful to living organisms; may occur naturally or as a result of human activities
a type of simple machine; a circular lever, usually a wheel with a groove where a rope can be placed and used to change the direction of a force
a change in the direction of a wave that occurs as it passes from one medium to another of different density
a resource that is replaced or restored, as it is used, by natural processes in a reasonable amount of time
a plan of inquiry that uses science process skills as tools to gather,organize, analyze, and communicate information
rock formed from layers of sediment that overlay and squeeze together or are chemically combined
a star and all the planets and other bodies that orbit it; the region in space where these bodies move
a large, gaseous, self-luminous body held together by gravity and powered by thermonuclear reactions
similar cells acting to perform a specific function; four basic types of tissue are muscle, connective, nerve, and epidermal
a vent or fissure in Earth's surface through which magma and its associated materials are expelled; generally a mountain-like structure
The path water takes as it is being cycled through the environment, including condensation, evaporation, and precipitation.
the natural processes that break down and change rock into soil,sand, and other materials
A material that readily allows electric charges to pass through it and therefor carries electricity well.
the remains of animal or plant life from past geologic ages that are now in a form suitable for use as a fuel (e.g., oil, coal, or natural gas)
the factor that is changed in an experiment in order to study changes in the dependent variable
theory of global dynamics in which Earth's crust is divided into a smaller number of large, rigid plates whose movements cause seismic activity along their borders
internal energy found by adding the kinetic energy of particles making up a substance
an event, condition, or factor that can be changed or controlled in order to study or test a hypothesis in a scientific experiment
a substance made up of at least two different elements held together by chemical bonds that can only be broken down into elements by chemical processes
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