Advertisement Upgrade to remove ads


science of life; examines how living things interact, how systems function, and how they function at a molecular level


anything that possesses all the characteristics of life; have an orderly structure, produce offspring, grow, develop, and adjust to changes in the environment


orderly structure of cells in an organism


evolution of a structure, behavior or internal process that enables an organism to respond to environmental factors and live to produce offspring


all of the changes that take place during the life of an organism; a characteristic of all living things


the ability to cause change; used to perform biological functions


biotic and abiotic surroundings to which an organism must constantly adjust; includes air, water, weather, temperature, other organisms, and many other factors


gradual change in a species through adaptations over time


increase in the amount of living material and formation of new structures in an organism; a characteristic of all living things


organism's regulation of its internal environment to maintain conditions suitable for survival; a characteristic of all living things


production of offspring by an organism; a characteristic of all living things


an organism's reaction to a change in its internal or external environment


group of organisms that can interbreed and produce fertile offspring in nature


anything in an organism's internal or external environment that causes the organism to react


in an experiment, the standard in which results are compared


Information obtained from experiments, sometimes called experimental results

independent variable

in an experiment, the condition that is tested because it affects the outcome of the experiment

dependent variable

in an experiment, the condition that results from changes in the independent variable


procedure that tests a hypothesis by collecting information under controlled conditions


explanation for a question or a problem that can be formally tested

safety symbol

symbol that warns you about a danger that may exist from chemicals, electricity, heat or experimental procedures

scientific methods

procedures that biologists and other scientists use to gather information and answer questions


explanation of natural phenomenon supported by a large body of scientific evidence obtained from many different investigations and observations


the moral principles and values held by humans


application of scientific research to society's needs and problems

Please allow access to your computer’s microphone to use Voice Recording.

Having trouble? Click here for help.

We can’t access your microphone!

Click the icon above to update your browser permissions above and try again


Reload the page to try again!


Press Cmd-0 to reset your zoom

Press Ctrl-0 to reset your zoom

It looks like your browser might be zoomed in or out. Your browser needs to be zoomed to a normal size to record audio.

Please upgrade Flash or install Chrome
to use Voice Recording.

For more help, see our troubleshooting page.

Your microphone is muted

For help fixing this issue, see this FAQ.

Star this term

You can study starred terms together

NEW! Voice Recording