6. Answer the following questions in four or five sentences. (a) Why is the atmosphere important to us? (b) How are nitrogen and carbon dioxide important? (c) Explain the main features of the troposphere. (d) Differentiate between the stratosphere and the mesosphere. (e) What do you know about the exosphere?
Answers
Answer:
The envelope of air around the earth is called atmosphere. it protect the Earth from excessive heat coming from the sun, it do not allow excessive heat to enter into the the Earth , if it happen then earth will be extremely hot we cannot live in it. And the heat to escape away from the Earth, if it happened then earth will be extremely cold and we all will frozen.
In the absence of atmosphere the earth would remain a frozen lifeless planet in space like any other planet.
human being do not use nitrogen directly but plant absorb nitrogen through the root from the soil. it is used by plants to support their growth and development ,thus nitrogen is indirectly useful to us.
plant use carbon dioxide during photosynthesis it make its food in the presence of sunlight water
and carbon dioxide.
Troposphere is the densest layer of the atmosphere. it is the portion where we live in and so it is most familiar to us. in this layer all weather changes take place.
Above the layer of troposphere lies calm and clear air which is called stratosphere. it provides visibility at the finest aircrafts of an fly through the lower layer of stratosphere. a special form of oxygen called ozone is found in the stratosphere this ozone layer is very important as it acts as a filter and absorbs harmful ultraviolet sun rays from reaching the Earth surface.
Above the stratosphere lies another layer known as Mesosphere ,it is a cold layer where temperature generally decreases with increasing altitude, meteors burn up in this layer.
Ion particles are found in exosphere which is electrically charged and play an important role in our wireless communication