Question

Treatment of polluted water is carried out with the help of
A. Lichens
B. Fungi
C. Ferns
D. Phytoplankton

Answer 1

Hint: Kingdom Fungi belong to the eukarya domain. They have a complex cellular structure. Most of the cellular organizations are almost equal to that of other eukaryotic cells. Fungi are saprophytes i.e. they feed on dead and decaying organic matter.

Complete answer: Treatment of polluted water includes physical processes and biological processes. The physical process includes methods such as filtration, sedimentation, and distillation.
Conventionally bacteria were used for the treatment of polluted water, but the problem with the use of bacteria in water treatment as it retains low-value bacterial biomass. Over bacterial use, filamentous fungi are used nowadays for water treatment. Some fungal species can remove organic and inorganic pollutants. Some technical difficulties of conventional bacterial use in wastewater treatment can be solved with the use of deeply growing mycelium of fungi. The technique of using the fungi in the biofiltration process is called mycofiltration. Here, filamentous fungi are used for water treatment. Few species like Oyster mushrooms can digest pollutants like petrochemicals and help to remove heavy metals. Several enzymes of fungi such as laccase enzymes can decompose lignin. Several other enzymes of various species help in the breakdown of toxins present in water. Laccase enzymes along with nanoparticle silica-di-oxide act as biocatalysts.
So, the correct answer to the given question is option B-Fungi.

Note: Over traditional use of bacteria, fungi are preferred for the filtration process of wastewater treatment. Sphaerotilus natans is fungi whose colonies are known as sewage fungus.