1. LT2.4 CARBON CYCLE
Learning Objectives:
• Describe the relationship between carbon and living organisms.
• List the major reservoirs of carbon on the Earth.
• Describe the movement of a carbon atom as it is exchanged between the
atmosphere, biosphere, geosphere, and hydrosphere.
• Describe the processes (fluxes) involved in recycling carbon between
organisms and the atmosphere, biosphere, geosphere, and hydrosphere.
• Identify carbon sinks and sources throughout the biosphere. (HONORS
ONLY)
2. It’s an element
It is a part of
ANYTHING
alive or once alive
Living things use
carbon for energy and
structure
What is Carbon?
3. Carbon is the fundamental building block of life!
All living organisms are built of carbon compounds. It is the
fundamental building block of life and an important component
of many chemical processes.
In the atmosphere, carbon is present primarily as carbon dioxide
(CO2), but also as other less abundant but climatically significant
gases, such as methane (CH4).
Without carbon, life would not exist as we know it. The well-
being and functioning of our planet depends on carbon and how
it cycles through the Earth's systems.
5. 1
4
ATMOSPHERE
Envelope of gases surrounding earth
GEOSPHERE/LITHOSPHERE
Rigid outer part of earth’s surface
2 HYDROSPHERE
All bodies of water
5
BIOSPHERE
Regions of earth’s surface occupied by living organisms
3
CRYOSPHERE
Frozen part of earth’s surface
Earth’s Systems – Spheres of Earth
7. CARBON CYCLE – KEY POINTS TO KNOW
• Carbon dioxide is a major
player in the Earth’s energy
balance.
• Life is fueled by carbon
compounds. Animals and
plants give off (release) carbon
dioxide during respiration.
• Plants use carbon dioxide
during photosynthesis and
build new carbon compounds.
oCarbon Reservoirs: the pool
where matter is stored
oCarbon Sink: more carbon
enters a pool than leaves it
oCarbon Source: more carbon
leaves a pool than enters
oCarbon Flux: the process
used to move carbon from
one reservoir to another
