Question

Lichens indicate SO₂ pollution because they
(a) show association between algae and fungi
(b) grow faster than others
(c) are sensitive to SO₂
(d) flourish in SO₂ rich environment

Answer 1

Answer:

grow faster than others

Answer 2

c. are sensitive to SO2

Explanation:

Lichens efficiently absorb sulphur when exposed to large quantity of sulphur dioxide in atmosphere.

Lichens are called bioindicators because if quantity of sulphur dioxide is more the lichens will die and only algae and fungi survive. The presence of only algae and fungi indicates high sulphur because lichens and algae live in symbiotic relation.

Lichens are sensitive to sulphur dioxide because they draw their nutrition from atmosphere instead of soil.