Carbon is important because:

• it is part of the carbon cycle

• it makes up part of all life forms on Earth

• it is related to oxygen

• it is found in excess in the ocean

Which of the following processes involves carbon?

• Photosynthesis

• Combustion

• Decay

• All of the above

Some aquatic organisms use calcium carbonite:

• for respiration

• to make carbonic acid

• to make their shells

• to make carbon sinks

Processes that put carbon into the air are called:

• Carbon Sinks

• Sources

• Photosynthesis

• Combustion

The natural carbon cycle:

• keeps the level of carbon in the environment in balance

• can upset the activities of man

• puts a lot of carbon back into the air

• reduces how much carbon is removed.