Question

Lichens indicate pollution of

• A. NO₂
• B. CO
• C. O₃
• D. SO₂

Answer 1

The correct option is D

SO₂

The correct option D.

Explanation of the correct option:

Option D:

1. Living things called "bioindicators" react to environmental changes in a very blatant way.
2. The symbiotic connection of fungi with algae or cyanobacteria results in the formation of lichen.
3. The algal component produces food through photosynthesis, and the fungal component is in charge of nutrient absorption.
4. Lichens, however, get their nutrition from the air rather than the earth. Thus, lichens' health will decline as a result of air pollution.
5. Since the resilient lichens primarily obtain their water and vital nutrients from the atmosphere rather than the soil, they serve as valuable bioindicators for air pollution, particularly sulfur dioxide pollution.
6. The fact that they can respond to air contaminants year-round is also beneficial.
7. They are less expensive to employ when assessing air pollution than the majority of physical or chemical detectors.
8. Because lichens bind radioactive metals and hazardous elemental contaminants in their fungal threads, where they accumulate over time, lichens can also be used to monitor these pollutants.
9. The history of the local air can then be ascertained by environmental scientists by evaluating this buildup.

Explanation of the incorrect options:

Option A:

1. Lichens do not indicate NO₂.

Option B:

1. Lichens do not indicate CO.

Option C:

1. Lichens do not indicate O₃.

Final answer: Lichens indicate pollution of SO₂.