Bronchial tubes in the lungs branch into ever-smaller structures, finally ending in alveoli. the alveoli act like what?
bellows
filters
springs
tiny bubbles
Figure 11.31 Bronchial tubes in the lungs branch into ever-smaller structures, finally ending in alveoli. The alveoli act like tiny bubbles. The surface tension of their mucous lining aids in exhalation and can prevent inhalation if too great.