Trachea Diffusion of oxygen and carbon dioxide takes place across the walls of the smallest tubes, called tracheoles, which penetrate tissues and even indent individual cells. Gas may be conducted through the respiratory system by means of active ventilation or passive diffusion. Unlike vertebrates, insects do not generally carry oxygen in their haemolymph. This is one of the factors that may limit their size. A tracheal tube may contain ridge-like circumferential rings of taenidia in various geometries such as loops or helices. Taenidia provide strength and flexibility to the trachea. In the head, thorax, or abdomen, tracheae may also be connected
What Is This? What Is This? What Is This (known prior to 1980 as Anthym) was a rock band that originated in Fairfax High School in California and would play numerous shows along the coast of California. It was formed by guitarist Hillel Slovak, drummer Jack Irons, vocalist Alain Johannes, and bassist Todd Strassman. Originally named Chain Reaction, the band would later change its name to Anthem, then later to Anthym (as there was already a band using the former moniker), and then finally to What Is This, which was a tongue-in-cheek reference to the reaction they usually received from first-time listeners. During