Question

Lichens are described as indicators of
A. Soil pollution
B. Air pollution
C. Water pollution
D. Agricultural productivity

Answer 1

A lichen is a composite organism that grows in a mutually beneficial symbiotic relationship from algae or cyanobacteria living among the filaments (hyphae) of the fungi.

Complete Answer:
Fungi, though they lack the green pigment chlorophyll, are incapable of photosynthesis. That is, in the form of carbohydrates, fungi do not extract light energy from the sun and produce their own nourishment. Instead, they need to look for outside food sources. Food is absorbed from organic substances, that is, compounds containing carbon, such as carbohydrates , fats, or proteins.

Algae and cyanobacteria can, on the other hand, perform photosynthesis, similar to plants. In fact, chloroplasts are adapted types of cyanobacteria, which are the site of photosynthesis in land plants. So when a fungus, which is the dominant partner in this relationship, combines to form a lichen with an algae (usually from the green algae) or cyanobacterium, It provides constant access to a source of food.The fungus regulates the association in a way that can be taken into account.

In a number of environmental processes, lichens are main actors. Cyanobacterial photobionts, for instance, indulge in nitrogen fixation. A process known as biological weathering also applies to lichens. Through producing such chemicals, the lichen mycobionts will break down rocks and release minerals.lichens are outstanding pollution indicators. Lichens can absorb contaminants such as heavy metals, carbon and sulphur into their thallus.

An indication of the levels present in the atmosphere is provided by extracting these pollutants. This method is known as biomonitoring for lichens. Lichens are known as sensitive air pollution indicators, especially for sulphur dioxide. This is linked, in part, to their special biology.

The correct Answer is option (C)Water pollution.

Note: Lichens is a perfect predictor of air quality. Lichens consume everything around them, such as air , water, toxins and nutrients. Toxins can be removed from lichens, and scientists can assess the levels of these toxins in the environment. Humans have used lichens for a number of uses, including clothing and decoration and even for eating. Lichens are currently used in toothpastes, deodorants, salves and other products and are investigated for their antibiotic properties.