205textnotes07

205textnotes07 - 4. The output element is composed of the...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
4. The output element is composed of the nerve terminals. They are the transmitting elements of the neuron. One neuron can form contacts with as many as 1000 other neurons. GLIAL CELLS (Fig. 8-5): In the CNS, glial cells are 10-50 times more numerous than neurons. Glial cells are implicated in various roles during development and injuries. They are supporting elements. Glial cells are not implicated in processing of information. In the CNS, the astrocytes , by far the most numerous of all glial cells, have long and numerous processes, their role is to induce the endothelial cells to form the blood-brain barrier. Some glial cells surround the nerve cell bodies and their axons (Fig. 8-6) : 1. In the CNS, oligodendrocytes are the glial cells that wrap around the axons to insulate them. 2. In the PNS, Schwann cells are the glial cells that insulate the axons by forming a myelin sheath that increases the speed of the electrical conduction. Chapter 8: The nervous system
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.
Ask a homework question - tutors are online