1. What is the Composition of the atmosphere?
Nitrogen: about ¾ of the atmosphere
Oxygen: 21% animals use it to release energy from their food
Carbon Dioxide : less than 1%, animals give off as a waste product
Other gases: argon and other trace gasses make up 1%
There is also water vapor and particles (solid and liquid)

2. What are the 4 layers of the atmosphere?
Troposphere: most of earths weather occurs here.
Stratosphere: This is the second layer and contains the ozone layer. Ozone is 3 oxygen atoms bonded together.
Mesosphere: protects earth from meteorites
Thermosphere: outermost layer of the atmosphere from 80 km high to outer space

3. Summarize. What's the air made of and what are the layers?
Work with your table partner to complete assess you understanding on 262 and 267