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 Love? (Twice song) What Is Love? (Twice song) "What Is Love?" (stylized as "What is Love?") is a song recorded by South Korean girl group Twice, the lead single of their fifth extended play of the same name. The song was released on April 9, 2018 by JYP Entertainment and distributed by Iriver. "What Is Love?" was written and composed by Park Jin-young, who previously produced "Signal", and it was arranged by Lee Woo-min "collapsedone", who co-produced "Knock Knock" and "Candy Pop". According to JYP Entertainment, the song is about "the love girls would dream about or imagine after learning about it through