Question

one must always breathe through the nose. Why?

Answer 1

because the hairs of nose purify air

Answer 2

Because the part nose is only connected with wind pipe and connected with lungs and only through lungs oxygen can pass and Carbo dioxide can come out only lungs can purify the oxygen and send to other parts of the body and if we breathe through mouth it is connected to food pipe and cannot do the proper breathing and leads to asthma

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