an explanation that is based on prior scientific research or observations and that can be tested
the process by which one or more substances change to produce one or more different substances
distinct thread-like structures located in the nucleus composed of the genetic information of the cell
substances formed by the joining of elements through chemical bonding. every molecule of a compound is the same.
Thinking that moves from general principles to specific cases. Two or more premises used to reach a conclusion. The conclusion is ALWAYS true if premises are true
radiation consisting of waves of energy associated with electric and magnetic fields resulting from the acceleration of an electric charge
the same as energy efficiency, a measure of how much useful work is accomplished by a particular input of energy into a system
a research method in which the investigator manipulates one ormore factors to observe their effect on some behavior or mental proce while controlling other relevent factors by random assingment of subjects
Occurs when an output of matter, energy, or information is fed back into the system as an input and leads to changes in that system.
first law of thermodynamics
states that energy is conserved. It is neither created nor destroyed underneath normal conditions.
a throughput of matter and energy within the system at certain rates, and outputs to the environment.
Preliminary scientific data, hypotheses, and models that have not been widely tested and accepted
the biochemical units of heredity that make up the chromosomes; a segment of DNA capable of synthesizing a protein
highly concentrated, found near the earth's surface and has great potential as a resource
law of conservation of energy
the law that states that energy cannot be created or destroyed but can be changed from one form to another
law of conservation of matter
the idea that matter is neither created nor destroyed in only changes form
Energythat is dispersed and has little ability to do useful work. Ex: low temp heat
a measure of how useful a substance is, based on availability, accessibility, and concentration
the smallest particle (one or more atoms) of a substance that has all the properties of that substance
natural radioactive decay
A nuclear change in which unstable isotopes spontaneously emit fast-moving chunks of matter (alpha or beta particles), high-energy radiation (gamma rays), or both at a fixed rate.
negative feedback loop
A feedback loop that causes a system to change in the opposite direction from which it is moving
Occurs when nuclei of certain isotopes spontaneously change or are made to change into nuclei of different isotopes.
A nuclear reaction in which a massive nucleus splits into smaller nuclei with the simultaneous release of energy
the combination of the nuclei of small atoms to form a larger nucleus; releases energy
a value that indicated the acidity or alkalinity of a solution on a scale of 0-14, based on the proportion of H+ ions.
stored energy that is latent but available for use. A rock poised at the top of a hill or water stored behind a dam are examples.
scientific (natural) law
A description of what scientists find happening in nature repeatedly in thesame way without exception.
is a testable assumption, or guess, often used to explain an observed phonomenon
second law of thermodynamics
any conversion of heat energy to useful work, some of the initial energy input is always converted to low quality, more dispersed, less useful energy.
Interaction of two or more factors or processes so that the combined effect is greater than the sum of their separate effects
the interaction of two or more agents or forces so that their combined effect is greater than the sum of their individual effects
a collection of structures, cycles, and processes that relate to and interact with each other
rate of flow of matter, energy and information into a system - a process that allows input to be changed so it is useful to system (text example: gasoline to car)