Insects don have lungs; how do they breathe?
Insects do not breathe using lungs as terrestrial vertebrates do; instead they use tracheal respiration in order to transport oxygen through their bodies. Insects have openings on the surface of their bodies called spiracles that lead to their tracheal systems. The air goes into the tracheal tubes and passes through the system of branching trachea. The circulatory system of insects, like that of other arthropods, is open: the heart pumps the hemolymph through arteries to open spaces surrounding the organs; when the heart relaxes, the hemolymph seeps back into the heart.
