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 More Can I Give What More Can I Give "What More Can I Give" (also "Todo Para Ti" in Spanish) is a song written by American singer Michael Jackson and recorded in 2001 by Jackson and a supergroup of singers following the September 11 attacks. The inspiration for the song had initially come to Jackson after a meeting with the President of South Africa Nelson Mandela in the late 1990s. The song was to be premiered at a Jackson concert, but the singer failed to perform it. The song also failed to gain an official release, despite the pop singer having stated that it