What are tracheae in arthropods?

Tracheae in arthropods serve as specialized respiratory structures that facilitate gas exchange. They are a system of air-filled tubes that extend throughout the body, allowing oxygen to diffuse directly into tissues and carbon dioxide to diffuse out. These tracheae are connected to the external environment through openings known as spiracles. This adaptation is particularly effective in terrestrial arthropods, where the tracheal system efficiently delivers oxygen directly to cells and tissues, thus supporting their metabolic needs.

The presence of spiracles, which can open and close, helps to regulate gas exchange and minimize water loss, an important adaptation for life on land. This system differentiates arthropods from other organisms that may use gills or lungs, illustrating their unique evolutionary approach to respiration in varying habitats.