What are the respiratory organs in cockroaches and grasshoppers?

Cockroaches and grasshoppers are insects, and they, like all insects, breathe through a tracheal system. 

The tracheal system is made up of a network of air-filled tubes called tracheae that run the length of the insect's body. 

These tubes carry oxygen from the spiracles (small openings on the body's sides) to the cells. The tracheae also transport carbon dioxide from cells to the spiracles, where it is expelled from the body.

This system is extremely efficient, allowing insects to exchange gases even in environments with limited oxygen. Unlike gills in aquatic animals or lungs in mammals, the tracheal system is unique to insects and plays an important role in their collective survival and success.