How Do Insects Breathe?
Insects do not have lungs, they breathe via tubes or tracheae, into which the air enters through tiny openings in the body surface. Inside the body, the tracheae become gradually smaller, reaching tissue and cells, into which the oxygen enters directly.
The insect's surface, which is covered by 1 exoskeleton, includes tiny spiracles, into which the oxygen enters. The spiracles can open and close, and they have filters to keep out dust. Air sacs are expanded to allow air 2 into the body. A branching network of thin tracheae carries the oxygen about the body and C0 out of the body. 2 The oxygen exchange does not take place via 3 blood like in mammals, but in the thinnest tracheae, called tracheoles. They are so tiny that they can deliver oxygen directly to the cells.