Q: Mammalian lungs have enormous number of minute alveoli (air sacs). It to allow
(a) : More space for increasing the volume of inspired air
(b) : More surface area for diffusion of gases
(c) : More spongy texture for keeping lungs in proper shape
(d) : More nerve supply to keep organs active when working
Answer: More surface area for diffusion of gases
Explanation:
Explanation:
In mammalian lungs each alveolar duct ends in a passage, called atrium , which leads into a number of rounded alveolar sacs . Each alveolar sac is studded with a large number of air sacs or alveoli. Alveoli are the sites of respiration.