Complete the following sentences.
(i) Nasal chambers are separated from the oral cavity by…
(ii) A film of…lines the alveoli to lower the surface tension.
(iii) Sound is produced by vibration of…located in the…
(iv) Left lung has… lobes, while right lung has…lobes.
(i) palate (ii) lecithin
(iii) vocal cords, larynx (iv) two, three