IN RESPIRATION WE TAKE OXYGEN FROM OUR NOSE .
FIRST THE O2 GAS IS ENTER INTO TWO NAUSTRIL THAN THEIR IS NASAL PASSAGE WHICH SECRETE MUCUS TO REMOVE IMPURITIES FROM IT.
THEN IT REACHES TO PHYRANX THEN LARYNX.
THEN IN TO TRACHEA THEN INTO BRONCHUS THEN INTO BRONCHULES
AND THEN INTO ALVEOLI IN LUNGS.
