All living organisms on the earth are protected from the harmful radiation coming from the sun by the ozone gas present in the stratosphere. Ozone gas is formed by the action of sunlight only oxygen of the air in the atmosphere. Starting atomic a height of about 16 km, the concentration of ozone becomes maximum at a height of about 23 km. This blanket of ozone around the earth is called ozone layer.
The radiation coming from sun consists of ultraviolet radiation. The ultraviolet radiation can penetrate deep into our body and cause diseases such as cataract, skin cancer, etc. Ozone layer absorbs the harmful ultraviolet radiation coming from the sun. Thus, the ozone layer protects animal and plant life only the earth from harmful effect of the ultraviolet radiation.