To put oxygen in hemoglobin in blood, so that it can be transported to the rest of your body.
Yes; lizards do use lungs to breathe.
they use their gills, skin, and later in life they use their lungs :)
Adults (and children) use their lungs all their lives.
Yes, snakes have lungs.
Yes. Koalas use lungs for respiration.
Lungs can be transplanted, if they are fresh.
You use your lungs to breath. Your heart pumps the blood round your body (including into and out of the lungs where gas exchange occurs when you breath).
Reptiles breathe by means of their lungs. Their respiratory system is similar to ours in structure.
breath
When you breathe.
Use lungs
No. Fish use gills instead of lungs. Marine mammals have lungs but don't breathe through a mouth or nose, they use a blow hole.