Prelims 2014 · Environment · Question 79
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.
Answer
1, 2 and 4 only
1. Volcanic action — Volcanoes release CO2 from Earth’s interior into the atmosphere. Correct.
2. Respiration — Living organisms respire and emit carbon dioxide as a by-product. Correct.
3. Photosynthesis — Green plants remove CO2 from the atmosphere to make food; they do not add it. Incorrect.
4. Decay of organic matter — Decomposition releases CO2 (and sometimes methane under anaerobic conditions) back into the carbon cycle. Correct.
So, 1, 2 and 4 only are correct.