Radial glial cell and OPCs can be generated from radial glial cells "in vitro", more evidence is yet needed to conclude whether this process also occurs in the developing brain. Recently, radial glia that exclusively generate upper-layer cortical neurons have also been discovered. Since upper cortical layers have expanded greatly in recent evolution, and are associated with higher-level information processing and thinking, radial glia have been implicated as important mediators of brain evolution. The best characterized and first widely accepted function of radial glia is their role as scaffolds for neuronal migration in the cerebral and cerebellar cortexes. This role can be easily
Carotid body sustentacular supportive cells. The carotid body contains the most vascularized tissue in the human body . The thyroid gland is very vascular, but not quite as much as the carotid body. The carotid body functions as a sensor: it responds to a stimulus, primarily O partial pressure, which is detected by the type I (glomus) cells, and triggers an action potential through the afferent fibers of the glossopharyngeal nerve, which relays the information to the central nervous system. The carotid body chemoreceptors are primarily sensitive to decreases in the partial pressure of oxygen (P). This is in contrast to the