What is not a required characteristic of all living things A. They require and energy source

B. Made up of 1 or more cells

C. They maintain stable internal conditions

D. They respond to changes in the enviroment

What is a food chain? a.different animals located in different communities b. energy transferred from the sun to plants and then to a series of living things c. rows of crops, such as lettuce, in a field d.animals using one another as food for energy and growth