Aim: How does carbon dioxide & oxygen get recycled in the carbon-

oxygen cycle?

DO NOW:1. Write out the equation for both photosynthesis & cellular respiration.

2. Why are these processes important for living things?

Importance of Carbon

• All living things are composed of carbon containing molecules

• Form the framework for proteins, carbohydrates & fats

• Glucose & carbon dioxide are made of carbon• When organisms eat other organisms, carbon

gets passed on!• Also contained in non-living or abiotic matter,

such as rocks & soil

Importance of Oxygen

• Important for life processes• Makes up molecules essential for life, such as

glucose & carbon dioxide• Q: Can you think of life processes which

require oxygen?

Recycling of Carbon & Oxygen• During photosynthesis, plants use CO2 & release O2

• CO2 released into the atmosphere, as a product of cellular respiration, by plants & animals

• Carbon stored in fossil fuels, such as coal, oil & natural gas & CO2 released into the air when fossil fuels are burned in a process called combustion

• Dead plant & animal matter contains carbon & oxygen, so decomposition recycles both elements back to the earth

Recycling of Carbon & Oxygen

• Decomposition uses O2 and releases CO2

• Oceans take up a lot of CO2

Animation

• http://studyjams.scholastic.com/studyjams/jams/science/ecosystems/carbon-cycle.htm

Brain-Pop Video

• https://www.brainpop.com/science/earthsystem/carboncycle/

Group Activity

• http://studyjams.scholastic.com/studyjams/jams/science/ecosystems/carbon-cycle.htm

Test Yourself!

Individual ActivityAnswer questions 1-4 on the carbon cycle handout.

• 1. Name the process in which plants convert CO2 into carbon compounds?

• 2. Where in the cycle does CO2 gets released into the atmosphere?

• 3. Name at least two sites on Earth that are reservoirs of carbon.

• 4. How are plants and animals useful in maintaining the balance of CO2 in the atmosphere?

Homework• Read txt. Pg. 47On loose-leaf, answer the following HW Questions by circling

the correct word to fill in the blanks for the carbon cycle!1) When plants perform (photosynthesis OR cellular respiration)

they take carbon dioxide out of the atmosphere and release oxygen.

2) When animals perform (photosynthesis OR cellular respiration) they take oxygen out of the atmosphere and release carbon dioxide.

3) Deforestation and the burning of fossil fuels (increases OR decreases) the amount of carbon dioxide in the atmosphere.

4) Decomposition (releases OR uses) carbon dioxide.5) Water (releases OR absorbs) carbon dioxide.