Question

what is carbon cycle

Answer 1

Carbon dioxide from the air gets taken in by plants who use photosynthesis to create sugars and starches which are then consumed by animals. The animals then inhale oxygen and exhale CO2 
(Respiration; breathing) back in the air and eventually they die and their body turns into fossil fuel over time. Industries take the fossil fuels and sell it to people as oil or gas. The gas is burned producing CO2 that is also put back into the air. This cycle starts all over again.

Answer 2

The series of processes by which carbon compounds are inter converted in the environment involving the incorporation of carbon dioxide into living tissue by photosynthesis and it's return to the atmosphere through respiration