if something is made up of something else then that something else can be found in that something & the earth 's atmosphere is made of 036 percent carbon dioxide by volume ->  carbon dioxide can be found in earth's atmosphere  carbon dioxide can be found in earth's atmosphere & carbon dioxide is a kind of gas ->  carbon dioxide is a kind of gas that can be found in earth's atmosphere  green plants provide food for themselves / animals / consumers by performing photosynthesis & to perform a process can mean to use a process ->  green plants use photosynthesis to provide food for themselves / animals / consumers  green plants use photosynthesis to provide food for themselves / animals / consumers ->  green plants use photosynthesis to make food  green plants use photosynthesis to make food & in order for a thing to provide something that thing must make that something & green plants are a kind of producer ->  some producers use photosynthesis to make food  if something is a raw material in a process then that something is required for that process & in the photosynthesis process carbon dioxide has the role of raw material ->  photosynthesis requires carbon dioxide  some producers use photosynthesis to make food & photosynthesis requires carbon dioxide ->  some producers use carbon dioxide to make food  carbon dioxide is a kind of gas that can be found in earth's atmosphere & some producers use carbon dioxide to make food -> carbon dioxide is a kind of gas that can be found in the atmosphere and is used by producers to make food