NUR 0012 Lecture 27 Ch. 11 Fundamentals of the Nervous System: IntroductionOutline of Last LectureI. Ch. 9 muscular physiology cont.A. Sliding filament theoryB. Neuromuscular junctionC. EC-coupling D. Muscle fiber contraction cycleE. Motor units F. Muscle twitchesOutline of Current LectureI. Ch. 11 nervous systemA. 3 basic parts1. Integration2. Afferent input3. Efferent outputB. Divisions of nervous system1. CNS2. PNS3. ANSThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.C. Neurological cellsD. Salutatory conductionCurrent LectureI. Ch. 11 nervous systemA. Has 3 basic parts 1. Integration: done either in brain or sometimes spinal cord2. Afferent (sensory) input: incoming3. Efferent (motor) output: going back out, can be conscious or autonomicallyB. Divisions of nervous system1. CNS: brain and spinal corda. bundles of axons: tractb. nuclei: collections of nerve cell bodies2. PNS: everything outside of brain and spinal corda. Axon tracts: nervesb. Cell bodies: gangliac. Afferent: sensory part1) Somatic: we perceive consciouslya) Touch, temp, vibrationb) Sight, sound, smell2) Visceral: from internal organs3. ANS: autonomic a. Motor input to smooth muscle, cardiac muscle, glandsb. Sympathetic: fight or flightc. ParasympatheticC. Neurological cells support and protect neurons1. Astrocytes: most abundant CNS neuroglia, create blood brain barrier with capillaries a. Help to clean up interstitial space so fluid surrounding neurons is kept relatively clean (no ions, hormones, etc.) 1) Necessary since nerve tissue is highly excitable and can die easily2. Microglial cells: defensive cells in CNS, relatives of white blood cellsa. Become phagocytic when something passes through blood brain barrier3. Ependymal cells: line cerebrospinal fluid-filled cavitiesa. Connected to brain or spinal cord tissueb. Ciliatedc. Push and produce CSF around CNS to provide nutrients etc. 4. Oligodendrocytes: have processes that form myelin sheaths around CNS nerve fibersa. Create myelin sheaths: increase AP speed along axons and some dendrites, tubes of phospholipid material5. Shwann cells: found outside CNS in PNSa. Myelinate nerve fibers6. Satellite cells: also found outside of the CNS in PNSa. Special glial cells that surround and protect cell bodiesD. Salutatory conduction: allows AP’s to travel very quicklya. Myelin is the most important factor in increasing conduction (sending AP) velocity1) Creates area of resistance: electrical signal jumps to next area of slightly lower resistance (typically the nodes, node of
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