GK
ECOLOGY BIODIVERSITY CONSERVATION ENVIRONMENTAL ISSUES
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Lichen
|
|
|
Orchid
|
|
|
Apricot
|
|
|
Tobacco
|
Detailed explanation-1: -Lichens can be used as air pollution indicators, especially of the concentration of sulfur dioxide in the atmosphere. If air is very badly polluted with sulphur dioxide there may be no lichens present. They are widely used as bio-indicators.
Detailed explanation-2: -Lichens are the most sensitive organisms to sulphur dioxide pollution and do not grow in areas with high levels of sulphur dioxides. Hence Lichens like Usnea are used as indicators of level of sulphur dioxide pollution.
Detailed explanation-3: -Final answer: Lichens are the most suitable indicators of pollution in the environment.
Detailed explanation-4: -Presence of sulphur dioxide in the atmosphere inhibits the growth of lichens. Therefore, they are used as an indicator to detect the presence of sulphur dioxide. Presence of sulphur dioxide reduces the rate of growth of lichens because lichens are highly sensitive towards sulphur dioxide.
Detailed explanation-5: -SO2 give out suffocating smell which indicates its presence.