Air science unit

Air ------------ on heating and --------------- on cooling.

Events related to weather take place in the --------------.

The -------------- is the layer of the atmosphere closest to the Earth's surface.

Space shuttles and the International Space Station are present in the ---------------.

The ---------------- is the layer of the atmosphere farthest from the Earth's surface.

The ozone layer is present in the ----------------.

Some bacteria can change nitrogen in air into a --------------- that plants can use.

Plants need the gas ----------- --------- to make their food.

The atmosphere is divided into five layers: ------------, ------------, -----------, ----------------,and --------------------.

Air is made up of ------------, oxygen, carbon dioxide, ------------- -----------------, and small amounts of other gases.

Oxygen is needed for --------------- and - -----------------.

Satellites orbit the Earth in the ------------.

The .................... helps to keep the Earth warm by trapping some heat from the Sun.

The layer of air surrounding the Earth is called the ---------------------.

Air is -------------- and has the same properties as --------------.

Meteors entering the Earth's atmosphere burn up in the --------------.