science education

Exploring Nature Science Education Resource:

Life Science, Earth Science, and Physical Science Resources for K-12

Oxygen Cycle Description and Assessment

Oxygen Cycle Description and Assessment

There is a cycle on Earth that replenishes the vital supply of oxygen that all living things need to survive.

Why is oxygen so important?

1) We use oxygen for respiration and it’s a process we can never stop doing until we die. We inhale oxygen and exhale carbon dioxide along with all animals, plants, and even bacteria.

2) When plants and animals die and decompose, that process uses oxygen too.

3) When you burn a fire it uses oxygen.

4) Even rusting metal uses oxygen. (This is called oxidation.)

Oxygen is needed for processes all over the Earth. With so many living using oxygen, it is important that the oxygen cycle is always making more!

Where do we get oxygen?

1) Some oxygen is made in the atmosphere, when sunlight breaks down water.

2) A lot of oxygen is stored in the oxide minerals of the Earth’s crust and mantle, called the lithosphere. This oxygen though, is bound to the rocks and can’t be used by living things.

3) Most oxygen available to us comes from photosynthesis made by plants on land and phytoplankton floating on the surface of the ocean. Photosynthesis is a process where the organism, powered by sunlight, takes carbon dioxide and water and releases oxygen and sugar. This is how they make energy for themselves and luckily, oxygen for us!
 

To make black and white copies for your whole class, see the copy-friendly version below.

Oxygen Cycle Description and Assessment
Oxygen Cycle Description and Assessment

Recommended Books & Products

For more information about the Oxygen Cycle with Activities for K-8: The Everything Kids Environment Book, Adams Media 2007

The Everything Kids Environment Book

Exploringnature.org has more than 2,000 illustrated animals. Read about them, color them, label them, learn to draw them.

cheetah, tiger, panda, fox, bear, cougar