Question

why it is not advisable to breath through mouth

Answer 1

It is not advisable to breath with mouth because air contains many harmful gases which can directly go to our lungs if we breath through mouth but breathing through nose . Nose have mucus inside it which purifies the air to some extent

Hope it helped

Answer 2

It is not advisable because while breathing through nose, mucous and cillia cells filter some dust particals but mouth does not have cilliated cell and mucous thus it do not filter air.