the nervous system
DESCRIPTION
ppt that gives a concise glimpse of the anatomy and the physiology of the nervous system. For students of 3r ESOTRANSCRIPT
“Mientras el cerebro sea un misterio, el Universo continuará siendo un misterio.” (Santiago Ramón y Cajal, Petilla de Aragón 1852-Madrid,1934. Premi Nobel de Medicina 1906)
Two kind of cells:Neurones and glial cells.NEURONES are the ones that trasmit the
nervous message.GLIAL CELLS assist the neurones in the CNS.
Nerve Cells and Astrocyte (SEM x2,250). This image is copyright Dennis Kunkel at www.DennisKunkel.com, used with permission.
MORE THAN 100 BILION IN The BRAIN
Some axons are wrapped in a myelin sheath formed by specialized glial cells known as Schwann cells. The gap between Schwann cells is known as the node of Ranvier, and serves as points along the neuron for generating a signal. Signals jumping from node to node travel hundreds of times faster than signals traveling along the surface of the axon. This allows your brain to communicate with your toes in a few thousandths of a second
SYNAPSES
Neurones never touch each other
That’s what we
can find in The
forebrain
Protected by the vertebral spine
Doesn’t reach the brain so it’s unconscious
It’s quick and automatic