Question

The atmospheric UV radiations are absorbed in the zone called as...
A. Stratosphere
B. Mesosphere
C. Thermosphere
D. Troposphere

Answer 1

Hint: Above the surface of earth different virtual atmospheric layers are formed for the differential study of the atmosphere with respect to the pressure and height.
The absorption of ultraviolet rays in the atmosphere is done by the ozone layer.

Complete answer: The atmosphere above the earth’s surface is divided into 6 main layers of the atmosphere.
1. Troposphere
2. Stratosphere
3. Mesosphere
4. Thermosphere
5. Ionosphere
6. Exosphere

The troposphere is the nearest layer to the surface of the earth. This lies from the surface of the earth to 8-15 kilometers of height. This part is most favorable for human survival.
All the vital gasses and normal temperature and pressure present in this part of the atmosphere.
The Stratosphere is present above the surface of the troposphere and extends up to the height of 50 kilometers. The good ozone layer is found in the upper part of the atmosphere in the stratosphere.
It acts as a protective shield for the troposphere and protects from UV radiation.
This layer has a dual function of absorption and scattering of UV radiations above the level of ozone.
The Mesosphere is next to the stratosphere and lies above the level of the stratosphere.
In the mesosphere mainly burning of meteors is observed.
The thermosphere extended to a height of 600 kilometers from the surface of the earth.
A mainly artificial satellite is present in this layer of the atmosphere.
The Ionosphere extended up to a height of 965 kilometers.
An abundant amount of electrons and ions are present in this layer.
This is the last layer of the atmosphere. It extended up to 1000 kilometres above the surface of the thermosphere. Hence ozone is responsible for the absorption of UV radiation which lies in the Stratosphere.

So, the correct answer is “Option A”.

Note: In today’s life due to the excessive invasion of greenhouse gases and gases like CFC the thickness of ozone reduces day by day and UV radiations can enter our troposphere.
Different international programs like the Montreal Protocol are launched for the protection of ozone.