Carbon Cycle

Gr 9 Science

Carbon Cycle

• Fourth most abundant element in universe • Building block of all living things• Main Pathway– in and out of living matter

Key Terms

Carbon Cycle- Circulation of carbon through ecosystems

Carbon- A non-metallic element found in coal, petroleum and natural gas. Major component of life.

Soil Respiration- Carbohydrates are oxidized and returned to the air by soil microorganisms that decompose dead animals

Atmosphere- layer of gasesFossil Fuels- Carbon-rich fuel from ancient

animals and plantsPhotosynthesis- Energy (sun)+ Water+ Carbon

dioxide Carbohydrates+ OxygenCellular Respiration- Glucose+ Oxygen

carbon dioxide+ water+ Energy (ATP)Decomposition- breakdown of matter by

bacteria and fungi

Biological Importance of Carbon

• All living organisms contain carbon• CO2 is found in all living organisms

• Plants use carbon dioxide and water to form simple sugars (photosynthesis)

Ecological Importance of Carbon

• Carbon is needed for life• Carbon dioxide is a greenhouse gas• Carbon is necessary for life, but carbon

dioxide can be harmful

• Greenhouse gases = atmospheric gases that prevent heat from leaving the atmosphere, thus increasing the temperature of the atmosphere

• Greenhouse effect = the warming of Earth as a result of greenhouse gases, which trap some of the energy that would otherwise leave Earth

• Since the Industrial Revolution, carbon dioxide levels, produced by the widespread use of burning fossil fuels (coal, oil, gas) for energy, have rises steadily.

• The increased concentration of carbon dioxide and other greenhouse gases (ex. Methane) in the atmosphere is the cause of global warming.

• Earth s average surface temperature has ′increased by about 0.74 ⁰C = Global Warming.