Question

Lichens indicate SO₂ pollution because they ______.

Options

• show association between algae and fungi

• grow faster than others

• are sensitive to SO₂

• flourish in SO₂ rich environment

Answer 1

Lichens indicate SO₂ pollution because they are sensitive to SO₂.

Explanation:

Symbiotic relationships between algae or cyanobacteria and fungi produce lichens. Lichens thrive in a variety of severe conditions. Most lichens are vulnerable to contaminants, notably epiphytic fruticose species and those harbouring cyanobacteria. As a result, they've been widely employed as SO₂ pollution indicators.