Anatomy Test 4 - Nervous system

dendrites and axon act as one "pole"c) bipolar neuronsfound in special sense organs -eyesd) anaxonic neuronsstar like (no obvious anatomical axon)located in central nervous tissue and in special sense organsNeuroglia "nerve glue" glial cells1. cannot generate impulse - but neuron can not send impulse w/out2. can divide - 75% of tumors formed by neuroglia3. supportive cells4. neuroglia of the CNSa) oligodendrocytes (CNS) - mylenating the axon- wrap aroundb) astrocytes "star like" - blood, brain barrier - make sure crosses over is safec) microglia "little eaters" - destroy debris, pathogensd) ependymal cells - line central canal of spinal cord and ventriclescerebral spinal fluid and maintain it, synthesize it, and circulate it5. neuroglia of PNSa) satellite cells - located in gangliab) schwann cell - myelinate axons - white matter(grey matter unmyelinated axons)4/7Dura Mater- most superficial - endosteum of cranium attached to bone - in certain spots splits and forms asinus--venous blood flowsArachnoid- wet saran wrap layer--spider web appearancePia Mater- outermost layer of brain in vagination - deepest layerDura Mater- attached tightly to crista galli of ethmoid bonealso divides 2 hemispheresleft + right falx cerebri **transverse fissure- tentorium cerebelli***- has a sinuscerebellum and occipital lobespinal cord- has same 3 layerspia mater towards spinal corddura mater not attached to vertebraepidural space- fat padcerebral spinal fluid - CSFproduced by capillaries + ependymal cells ---choroid plexusbring fluid in from bloodventricles- fluid w/inchoroid plexus floor of lateral ventricle, roof of 3rd, back of 4thfluid baths brain and spinal cordarachnoid granulations reabsorb the fluid - arachnoid villi absorbevery 8 hours recirculatedgranulations formed 3-4 years oldbefore that done by capillariesif not work well - **hydrocephalus- fluid not drawn backknow basic description and flow of cerebral spinal fluidcerebral aqueduct - goes to 4th ventricle