Lungs are like sponges your lungs
are spongy organs filled with millions
of air passages. These passages look
like a tree trunk with many different
sized root. Your windpipe or trachea tra-lee-uh branches into two main passages which is called branchi.
The branchi branch into smaller
and smaller tubes which is called
branchioles bron-key-O-lees.
At the end of each of these
tiny tubes is a tiny air sac.
Oxgen seeps through the walls
of the air sacs and travels into
the bloodstream. In addition,
small blood vessels with thin
walls wrap around the air
sacs and exchange carbon
dixide for oxgen. The lung
have five lobes. The right lung
have three lobes and the left lung
have two lobes.