In the central nervous system, there are three different layers that cover the spinal cord and brain. These are called the meninges, and their three levels consist of the: pia, arachnoid, and dura mater. Bone is situated above these layers, followed by periosteum (a fibrous membrane that covers bone) and skin.The dura mater is the top layer of the meninges, lying beneath the bone tissue.This material at times opens into sinus cavities (spaces) located around the skull.he dura mater is the top layer of the meninges, lying beneath the bone tissue. This material at times opens into sinus cavities (spaces) located around the skull.
Planet Earth Making Mountains Planet Earth filmmakers came out in the rugged mountains of Nepal in hopes of filming the elusive snow leopard for the Mountains episode. 01:51.
Planet Earth was the second attempt by Roddenberry to create a weekly series set on a post-apocalyptic future Earth. The previous pilot was Genesis II, and it featured many of the concepts and characters later redeveloped in Planet Earth.here and in the Planet Earth scene, the heroes witness the effect of their own violence on children, forcing them to rethink the use of forceâa very effective and intelligent pacifistic touch from Roddenberry. This article is about the science fiction film. For the BBC documentary, see Planet Earth (TV series) .