Answer:
how does it work
The oxygen is air throught the nose (obviously)
the cilia present in the nostrils will help purify the air which the person has taken in during inhalation
now the oxygen travels through the throat of the person and hence reaches the lungs,(brochus and then to bronchioles)
then the oxygen reaches the alveoli present in the lungs
the exchange of gases occur in the alveoli,carbon dioxide is given out and oxygen is taken inside the aveoli which will later convert deoxygenated blood to oxygenated (as now there is oxygen in blood)
now,the carbon dioxide which was given out by the alveoli will be released outside the body through exhalation.
the diaphragm moves upwards during exhalation hence decreasing the thoraic volume.
the diaphragm moves downwards during inhalation hence increasing the thoraic volume.
larynx is the voice box,epiglottis does not allow the food to enter into the wind pipe.
Need further Step-by-step explanation ?
I hope this helps