Question

Que.mammalian lungs have enormous number of minute alveoli. it is allow to:
a)more space for increasing the volume of inspired air
b)more surface area for diffusion of gaeses
c)more spongy texture for keeping lungs in proper shape
d)more nerve supply to keep organs active when working..
need help with reason

Answer 1

b) more surface area for diffusion of gases.

Answer 2

it can also be a) i m confused in a) and b)

Answer 3

no, it is not a). you compare two lungs of equal volume, one with alveoli and one without. the difference is the surface area.

just for number freaks out there: the volume of a human lung is about 5 to 6 litres. its surface area is about 250 square meters! w/o alveoli, the surface of a 6 liter lung would be around 0.05 square meters, maximum.
this allows for a rather quick diffusion. diffusion is a slow process, normally, this is why the increased surface is needed.

Answer 4

thnQ

Answer 5

b). checked.