A control variable is: A. Measured to show the effect of a change. B. Collected to draw conclusions. C. Changed to test a hypothesis. D. Kept the same to make an experiment a fair test.

Use the drop-down menu to match the following definitions to the corresponding terms. the total variety of organisms that live in the biosphere a group of organisms that breed and produce offspring that can breed all of the biotic and abiotic factors in an area

Which is an example of a decomposer? a. bear b.algae c.grass d.bacteria d bacteria

The finches on the galapagos island were similar in form except for variations of their beaks. darwin observed that these variations were useful for: attracting a mate defending territory building nests gathering food