Lungs are made up of air-filled sacs, the alveoli.
They do not collapse even after forceful expiration,
because of
(a) inspiratory reserve volume
(b) tidal volume
(c) expiratory reserve volume
(d) residual volume.
They do not collapse even after forceful expiration,
because of
(a) inspiratory reserve volume
(b) tidal volume
(c) expiratory reserve volume
(d) residual volume.