An organized way of gathering and analyzing evidence to learn about the natural world.


the act of noticing and describing events or processes in a careful , orderly way


logical conclusion based on observations


possible explanation for a set of observations or possible answer to a scientific question

controlled experiment

an experiment in which only one variable is manipulated at a time

independent variable

The experimental factor that is manipulated; the variable whose effect is being studied.

dependent variable

variable that changes as a result of a change in the independent variable

control group

the group that does not receive the experimental treatment.


information gathered from observations


a decision about the hypothesis based on the results of the experiment


an explanation using an integrated set of principles that organizes observations and predicts behaviors or events


a particular preference or point of view that is personal rather than scientific


the study of life


the ability of a living thing to keep conditions inside its body constant


the passing of traits from parent to offspring


a theory that explains how random changes in genetic material and competition for scarce resources cause species to change gradually


the part of earth where life exists


all of the chemical reactions that occur within an organism


a change in an organisms surroundings that causes the organism to react


a complex molecule containing the genetic information that makes up the chromosomes

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