Create an account
Animals give off carbon dioxide...
which plants use to make food... plants give off oxygen, which animals need to survive.
holds heat close to Earth's surface and protects living things from the Sun's harmful rays.
Cooling water causes condensation, a change from gas to liquid...
When liquid water freezes, it changes into ice.
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 and try again
Reload the page to try again!Reload
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