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प्रश्न
Explain the following observations very briefly
Breathing through mouth may harm you.
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उत्तर
There are many dust particles, gases and water vapours present in the air that we breathe. When we inhale through nostrils, the entry of these harmful particles is prevented by the fine hair and mucus present in the nose as they filter the air but when we breathe through the mouth there’s no such filtering of particles. Thus, they enter our body, reach the respiratory tract and make us ill.
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