Overview of the nervous systemCentralnervoussystemInformationprocessingmotorsensoryinformationcommandswithinwithinafferentefferentPeripheralnervousdivisiondivisionincludessystemAutonomicSomaticnervoussystemnervoussystemsympatheticparasympatheticdivisiondivisionspecialsensorysomaticreceptorssensoryreceptors-smoothskeletalmusclemuscle-cardiacvisceralsensoryreceptorsmuscle-glands
Central nervous system Information processing sensory information within afferent division motor commands within efferent division Somatic nervous system Autonomic nervous system parasympathetic division sympathetic division skeletal muscle -smooth muscle -cardiac muscle -glands special sensory receptors somatic sensory receptors visceral sensory receptors Peripheral nervous includes system Overview of the nervous system
lll.Cellularorganizationof nervous systemThefundamentaltissueofnervoussystemisnervoustissue.NeuronNsNeuroglia(Glial cell)100~300billionnervecells(neurons)Perhaps 1Otimes that many supporting cells(neuroglia),butglialcellsaresmallerthantheneurons
III. Cellular organization of nervous system The fundamental tissue of nervous system is nervous tissue. Neuron Neuroglia (Glial cell) N S 100~300 billion nerve cells (neurons) Perhaps 10times that many supporting cells (neuroglia), but glial cells are smaller than the neurons
i. NeuronIt is the basic unit of structure and functionof nervous system,whichperformthefunction of receiving stimulation andconductingnervous impulse.(1)ConstructionofneuronNissl bodycell bodyneurofibrilrlliuntneurondendriteprocessaxonFioiftTUT(rgramidalcill iac
i. Neuron It is the basic unit of structure and function of nervous system, which perform the function of receiving stimulation and conducting nervous impulse. (1)Construction of neuron neuron cell body process dendrite axon Nissl body neurofibril
Basic structureof a representativeneuronaxoncell bodydendritesaxonterminals(soma)CetbodySynapticDendritesterminalsStimulatedbyenvironmentaContains the nucteusConducts nerveimpulseAffectanother(actionpotential)towardchanoesortheactivitiesofandtmitochondrianeuronoreffectorothercellsribosomes,etc.symaptic terminals(muscle, giand, etc.)The neuron transmits electric signals like an electric wire:The perikaryon (cell body) is the metabolic and genetic center of a neuron .Dendrites, short branches, extend from the neuron. These input channelsreceiveinformation from other neurons or sensory cells (cells that receive informationfromtheenvironment)Axon, alongbranch,extendsfromtheneuronas its outputchannel.Theneuronsends messages along the axon to other neurons or directly to muscles or glands
The neuron transmits electric signals like an electric wire: • The perikaryon (cell body) is the metabolic and genetic center of a neuron . • Dendrites, short branches, extend from the neuron. These input channelsreceive information from other neurons or sensory cells (cells that receive information from the environment). • Axon, a long branch, extends from the neuron as its output channel. The neuron sends messages along the axon to other neurons or directly to muscles or glands. dendrites cell body (soma) axon axon terminals Basic structure of a representative neuron
DifferentsizesandshapesofneuronB(Achuol sizeCell bodies range from5-100umindiameterAxonsvaryfrom1mm-1m or moreA:Purkinje cellEB: granule cellC: projection cell from theFinf.olivary nucleusD:spinal cordmotorneuronE:pyramidal neuronF:olfactory receptor neuronG: dorsal root ganglion cell
Different sizes and shapes of neuron Cell bodies range from 5-100um in diameter Axons vary from 1mm- 1m or more A: Purkinje cell B: granule cell C: projection cell from the inf. olivary nucleus D:spinal cord motor neuron E: pyramidal neuron F: olfactory receptor neuron G: dorsal root ganglion cell A B C D E F G