Q. Which of the following adds/add carbon dioxide to the carbon cycle on the planet Earth?
- Volcanic action
- Respiration
- Photosynthesis
- Decay of organic matter
Select the correct answer using the code given below.
- 1 and 3 only
- 2 only
- 1, 2 and 4 only
- 1, 2, 3 and 4
Answer: (c) 1, 2 and 4 only
Notes:
- The Process of photosynthesis takes up Carbon dioxide and release oxygen. Hence photosynthesis does not add carbon dioxide to the carbon cycle.
- Volcanic action leads to the release of Carbon dioxide.
- Respiration is the movement of oxygen from the outside environment to the cells within tissues and the release of carbon dioxide in the opposite direction.
- The process of decomposition releases Carbon dioxide.
Carbon cycle
- Carbon cycle shows the movement of carbon in elemental and combined states on earth. Diamond and graphite are the elemental forms of carbon and in a combined state, it is found as carbonates in minerals and as carbon dioxide gas in the atmosphere.
- Carbon cycle is the process where carbon compounds are interchanged among the biosphere, geosphere, pedosphere, hydrosphere, and atmosphere of the earth.
- Carbon Cycle Steps
- Carbon present in the atmosphere is absorbed by plants for photosynthesis.
- These plants are then consumed by animals and carbon gets bioaccumulated into their bodies.
- These animals and plants eventually die, and upon decomposing, carbon is released back into the atmosphere.
- Some of the carbon that is not released back into the atmosphere eventually become fossil fuels.
- These fossil fuels are then used for man-made activities, which pump more carbon back into the atmosphere.

