Does a Cockroach Need Oxygen?
WouterIn order to find out whether a cockroach needs oxygen or not, researchers examined the tracheae of cockroaches. Roaches have a complex tracheal system, similar to plants’ stomata, which carry water from the cells. A well-developed trachea indicates that a cockroach is getting adequate oxygen, while a thin one suggests that it is not getting enough.
Roaches have a tracheal system consisting of two spiracles. These spiracles allow the insect to breathe and deliver oxygen to the cells. After they have exhaled, they close the spiracles. This allows the insect to keep carbon dioxide levels in check and regulate the amount of water lost.
In germfree cockroaches, the anterior hindgut has a low oxygen partial pressure of 1 kPa, which is due to respiratory activity in the gut epithelium. This may indicate that oxygen consumption in the midgut is significant. Germfree nymphs also produce small amounts of lactate, which may be the result of a switch from aerobic to anaerobic metabolism.
In contrast to humans, cockroaches have a mechanically ventilated respiratory system. Their pumping movements drive air out of spiracles and draw in air, changing the pressure inside their tracheae. The spiracles are not the only source of oxygen for the cockroach, however, as they can survive for long periods of time without breathing.
