When trees are cut, amount of oxygen
(a) decreases
(b) increases
(c) both (a) and (b)
(d) remains same
Answers
Answer:-
a) Decreases.
Explanation:-
Trees we know are responsible for the most crucial process that sustains life on earth i.e. photosynthesis.
Photosynthesis is the process by which green plants prepare food in the presence of sunlight and chlorophyll by taking CO2 and moisture from the atmosphere. It liberates O2 as a by-product. Hence, cutting down of trees not only decreases the amount of O2 but also increases the amount of CO2 liberated.
The following equation illustrates photosynthesis:-
6CO2 + 12H2O -------> C6H12O6 + 6O2 + 6H2O
The amount of O2 liberated by trees contributes the major share of O2 in the atmosphere. The tropical rain forests which occupy only 6% of total land surface of the earth, alone contributes 40% (approx.) of the total oxygen content of the atmosphere.