How is the alveoli adapted to carry out gas exchange?

They give the lungs a really big surface area. They have moist, thin walls, gases dissolve in the moisture helping them to pass across the gas exchange surface.

1) the mayans built pyramids just like the egyptians. the mayans also used hieroglyphics like them.2) power was passed down by family. for example, if the father dies, the son would be the next king.3)they both built pyramids for their structures.4)the main crop for the mayans was maize.5)they also grew manioc, beans,  squash,  amaranth, and chile peppers.