Question

the carbon cycle describes the movement of carbon between living things, the atmosphere, the oceans, and earths crust.
select the true statements.
photosynthesis takes more co₂ out of the atmosphere than any other process.
the total amount of carbon on earth does not change significantly from year to year.
the burning of fossil fuels is a carbon sink.
the ocean absorbs more co₂ from the atmosphere than it releases.

Explanation:

• Photosynthesis: It is a major process that takes \(CO_2\) from the atmosphere. Plants use \(CO_2\), water and sunlight to produce glucose and oxygen. Among natural processes, it is a significant sink for atmospheric \(CO_2\).
• Total carbon on Earth: According to the law of conservation of mass (in the context of the carbon cycle), carbon is recycled rather than created or destroyed in significant amounts on a short - term (year - to - year) basis. It just changes its form (e.g., from \(CO_2\) in the atmosphere to organic carbon in living organisms or carbonate rocks).
• Burning of fossil fuels: A carbon sink is a reservoir that absorbs more carbon than it releases. Burning fossil fuels (\(C_xH_y+O_2

ightarrow CO_2 + H_2O\)) releases \(CO_2\) into the atmosphere. So, it is a carbon source, not a sink.

• Ocean and \(CO_2\): The ocean is a carbon sink. It absorbs \(CO_2\) from the atmosphere (\(CO_2 + H_2O

ightleftharpoons H_2CO_3\)) and also releases some \(CO_2\) back. But over all, it absorbs more \(CO_2\) from the atmosphere than it releases.

Answer:

• Photosynthesis takes more \(CO_2\) out of the atmosphere than any other process.
• The total amount of carbon on Earth does not change significantly from year to year.
• The ocean absorbs more \(CO_2\) from the atmosphere than it releases.