《医学英语中枢神经系统幻灯片.ppt》由会员分享，可在线阅读，更多相关《医学英语中枢神经系统幻灯片.ppt（11页珍藏版）》请在taowenge.com淘文阁网|工程机械CAD图纸|机械工程制图|CAD装配图下载|SolidWorks_CaTia_CAD_UG_PROE_设计图分享下载上搜索。
1、医学英语中枢神经系统第1页，共11页，编辑于2022年，星期五One way to classify neurons is by the One way to classify neurons is by the number of extensionsnumber of extensions that that extend from the neurons cell body(soma).extend from the neurons cell body(soma).Bipolar neuronsBipolar neurons have two processes extending ha
2、ve two processes extending from the cell body(examples:retinal cells,from the cell body(examples:retinal cells,olfactory epithelium cells).olfactory epithelium cells).Pseudo-uni-polar cellsPseudo-uni-polar cells (example:dorsal root ganglion(example:dorsal root ganglion cells).Actually,these cells h
3、ave 2 cells).Actually,these cells have 2 axons rather than an axon and axons rather than an axon and dendrite.One axon extends dendrite.One axon extends centrally toward the spinal cord,centrally toward the spinal cord,the other axon extends toward the the other axon extends toward the skin or muscl
4、e.skin or muscle.Multipolar neuronsMultipolar neurons have many have many processes that extend from the cell body.processes that extend from the cell body.However,each neuron has only one However,each neuron has only one axon(examples:spinal motor neurons,axon(examples:spinal motor neurons,pyramida
5、l neurons,Purkinje cells).pyramidal neurons,Purkinje cells).Types of neurons.Types of neurons.第2页，共11页，编辑于2022年，星期五Neurons can also be classified by the Neurons can also be classified by the direction that direction that they send information:they send information:Sensory(or afferent)neurons:Sensory
6、(or afferent)neurons:send information from send information from sensory receptors(e.g.,in skin,eyes,nose,tongue,ears)sensory receptors(e.g.,in skin,eyes,nose,tongue,ears)TOWARDTOWARD the central nervous system.the central nervous system.Motor(or efferent)neurons:Motor(or efferent)neurons:send infor
7、mation send information AWAYAWAY from the central nervous system to muscles or from the central nervous system to muscles or glands.glands.Interneurons:Interneurons:send information send information between between sensory sensory neuronsneurons and and motor neuronsmotor neurons.Most interneurons a
8、re located.Most interneurons are located in the central nervous system.in the central nervous system.Types of neurons.Types of neurons.第3页，共11页，编辑于2022年，星期五 A single neuron consist of:A single neuron consist of:CELL BODYCELL BODY:is the metabolic center of the neuron,contains the Nucleus:is the meta
9、bolic center of the neuron,contains the Nucleus and Mitochondrion.and Mitochondrion.DENDRITESDENDRITES:convey incoming messages to the cell body.:convey incoming messages to the cell body.AXON HILLOCKAXON HILLOCK:a cone like region from where an axon arises.:a cone like region from where an axon ari
10、ses.AXONSAXONS:generates nerve impulses and topically conduct them away from the:generates nerve impulses and topically conduct them away from the cell body.A nerve is a group of axons”.cell body.A nerve is a group of axons”.Presynaptic terminals:Presynaptic terminals:The swollen,distal end of an ax
11、on;contains a The swollen,distal end of an axon;contains a neurotransmitter substance within synaptic vesicles.Also called synaptic ending.neurotransmitter substance within synaptic vesicles.Also called synaptic ending.第4页，共11页，编辑于2022年，星期五AxonsAxons Take information away from Take information away
12、from the cell body the cell body Smooth Surface Smooth Surface Generally only 1 axon per cell Generally only 1 axon per cell No ribosomes No ribosomes Can have myelin Can have myelin Branch further from the cell bodyBranch further from the cell body DendritesDendrites Bring information to the cell B
13、ring information to the cell body body Rough Surface(dendritic Rough Surface(dendritic spines)spines)Usually many dendrites Usually many dendrites per cell per cell Have ribosomes Have ribosomes No No myelin insulationmyelin insulation Branch near the cell bodyBranch near the cell bodyThere are seve
14、ral differences between axons and dendrites:There are several differences between axons and dendrites:第5页，共11页，编辑于2022年，星期五NEUROGLIAL cells-there are six types of supporting cells;four in the CNS and two in the PNS第6页，共11页，编辑于2022年，星期五第7页，共11页，编辑于2022年，星期五第8页，共11页，编辑于2022年，星期五第9页，共11页，编辑于2022年，星期五第10页，共11页，编辑于2022年，星期五The Meninges and Cerebrospinal Fluid第11页，共11页，编辑于2022年，星期五