Question

Pollution indicator plants
(a) Are resistance to pollution
(b) Can purify the atmosphere
(c) Are very sensitive to pollution
(d) Are very sensitive to pollutants

Answer 1

Pollution indicators can tell us about the cumulative effects of different pollutants in the ecosystem and about how long a problem may have been present, which physical and chemical testing cannot.

Complete step by step answer: The plants that are used because the indicators to the pollutants are very sensitive to the pollutants are such that they either grow disease symptoms or conclude to develop when these particular pollutants are present within the air, water, or soil. For instance, Salvia and Pinus are responsive to ozone and sulfur dioxide pollution, and that they appear with red spots and curling of the leaves. Petunia and Chrysanthemum are sensitive to the peroxy- acetyl nitrate and they show the destruction of the chlorophyll. Lichens stop to enlarge in the sulfur dioxide pollution.

Additional information: The knowledge of plant indicators is often helpful to work out local soil, thus it is often decided which crops should be cultivated during a particular soil and which soil should be left for pasture or other purposes. Plant indicators also want to determine the optimum use of natural resources for the forest, pasture, and agricultural crops. Many plants also specify the existence of particular minerals or metal. So the presence of valuables is often detected by the expansion of the precise plant in a region. So, the correct answer is 'Are very sensitive to pollutants'.

Note:
- Plant indicators also determine the optimum use of natural resources for the forest, pasture, and agricultural crops.
- Plants of huge species are better indicators than plants of small species.
- Before depending on a single species or group of species as indicators, there should be huge field evidence.
- Numerical relationships between species, population, and whole communities often provide more reliable indicators than single species.