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
The Body of the Dead Christ in the Tomb The Body of the Dead Christ in the Tomb The Body of the Dead Christ in the Tomb is an oil and tempera on limewood painting created by the German artist and printmaker Hans Holbein the Younger between 1520–22. The work shows a life-size, grotesque depiction of the stretched and unnaturally thin body of Jesus Christ lying in his tomb. Holbein shows the dead Son of God after he has suffered the fate of an ordinary human. The painting is especially notable for its dramatic dimensions (30.5 cm x 200 cm), and the fact that Christ's face, hands and feet,