Question

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

Answer 1

Hint: Treatment of polluted water comprises physical processes and biological processes. The physical process involves methods say as filtration, sedimentation, and distillation. Conventionally bacteria were first time utilised for the treatment of polluted water, but the problem with the use of bacteria in water treatment as it retains low-value bacterial biomass.

Complete answer:
Over bacteria, filamentous fungi are used in today's times for water treatment. Some fungal species help to remove organic and inorganic pollutants. Some technical difficulties of conventional bacteria utilized in wastewater treatment can be solved with the use of deeply growing mycelium of fungi. The technique of using the fungi in the bio filtration process is termed as mycofiltration.

Now let us match this with the options given:
Lichens : The symbiotic relationship of fungi with those of algae is termed as lichen. They are a good source of pollution.
Fungi : Few species of fungi such as Oyster mushrooms can digest pollutants like petrochemicals and help to remove heavy metals. Several enzymes of fungi such as laccase enzymes can decompose lignin so it helps in treatment of water pollution.
Ferns : gymnosperms such as Ferns are used to treat the red tides and also soil erosion.
Phytoplankton : They are a good source to detect soil erosion.

Hence, the correct answer is option (B)

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