What are the valves that open and close an insect's respiratory system known as?

The valves that open and close an insect's respiratory system are known as spiracles. Spiracles are small openings located along the sides of an insect's body that allow air to enter and exit the tracheal system, which is the network of tubes that delivers oxygen directly to the insect's tissues. These valves play a crucial role in regulating gas exchange, enabling the insect to control its breathing by opening and closing the spiracles as needed, depending on environmental conditions and the insect's activity level.

Other terms in the context of insect respiration include tracheae, which are the actual tubes that transport the air from the spiracles to the internal tissues, but they do not function as the openings themselves. Stomata refer to similar structures found in plants, and the prothorax is a segment of the insect's body but has no direct relevance to the respiratory system. Understanding the specific function of spiracles is key in studying how insects manage respiration in their unique physiology.