STAAR REVIEW

What you don't remember from class

Carbon dioxide

Carbon dioxide is a gas that is made up of one carbon atom with is (CO2) and is what plants use to make food .Humans and animals don't need to breath in they breath it out.

Oxygen

Is an gas that humans breath in to survive. Plants let out to help humans while we help them by breathing out.

How the cycle works is we as humans let out CO2 , and give it to the plants while the plants let out the O2