Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that...
Transcript of Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that...
![Page 1: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/1.jpg)
NervousSystemLesson11
![Page 2: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/2.jpg)
ReflexArcs1. Patellarreflex
• Causeslegtokickup
2. Achillesreflex• Causesfoottojerkforward
3. Tricepsreflex• Causesarmtostraighten
4. Babinskireflex
4. PupilDilationReflex• Causespupiltodilateinthedarkandconstrictinlight
![Page 3: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/3.jpg)
![Page 4: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/4.jpg)
![Page 5: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/5.jpg)
LearningGoals
1. Howisthenervoussystemdivided?
2. Whatarethecomponentsofaneuron?
3. Howdoesaneuralcircuitwork?
4. Whatisareflexarc?
![Page 6: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/6.jpg)
OrganizationoftheNervousSystem
NervousSystem:complexnetworkofnervesandcellsthatcarrymessagestoandfromthebrainandspinalcordtothebody
2functionalsystems:• CentralNervousSystem(CNS)• Brainandspinalcord
• PeripheralNervousSystem(PNS)• NervesthatcarryinformationbetweenorgansandCNS
![Page 7: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/7.jpg)
![Page 8: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/8.jpg)
PeripheralNervousSystem
1. Sensory(afferent)somaticnervesà relayinformationaboutenvironmenttoCNS
a) Somaticb) Autonomic
2. Motor(efferent)somaticnervesà initiateanappropriateresponse
![Page 9: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/9.jpg)
PeripheralNervousSystem
1. Somaticsystemà skeletalmuscle,skin,sensoryorgans(voluntary)
2. Autonomicsystemà internalorgancontroli.e.smoothmusclesandglands(involuntary)a) Sympatheticà nervecellsthatpreparebodyforstress(“fightorflight”)b) Parasympatheticà nervecellsthatreturnthebodytoanormalstateafter
stress(“restordigest”)
![Page 10: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/10.jpg)
Neuron(nervecell)• Specializednervecellthatisthefunctionalunit ofthenervoussystem• Allowsorganismstoreceive andrespond tobothinternalandexternalstimuli
3mainparts1. Dendrites – receiveinformationà Cellbody2. Cellbody – informationistransmittedawayfromthebodyà axon3. Axon– informationissentalongtheaxonà neuron,muscle,organ,gland
![Page 11: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/11.jpg)
Theneuron(nervecell)Aneuron isaspecializednervecellthatisthefunctionalunitofthenervoussystem
1. Cellbody• Containsnucleusandmostcellorganelles
2. Dendrites• Highlybranchedprojectionsthatreceivesignalsandtransmitsthemtowardsthecellbody
3. Axons• Conductssignalstowardsanotherneuronoraneffector
4. Axonterminal• Enablesthesignalstothetransmittedfromoneneurontoanotheroraneffector
![Page 12: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/12.jpg)
Theneuron(nervecell)
5. Nucleus• OrganellewhereDNAisstored
6. Schwanncells• Aglialcell;formtightlywrappedlayersofplasmamembranecalledmyelinsheath
• Glialcells:Containsnucleusandmostcellorganelles;donot conductsignals;providesupportandnutrientstoneurons
7. Myelinsheath• Fattyproteinthatactsaselectricalinsulatorsandhelpincreasespeedofimpulses
8. NodesofRanvier• GapbetweenSchwanncellswhichexposetheaxondirectlytoextracellularfluids
![Page 13: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/13.jpg)
NeuralCircuitConsistsof5components:
1. Receptor• Detectionofstimulibysensoryreceptorsonafferent
neurons
2. Afferentneuron(sensor)• Transmission(movement)ofamessagealongafferentneuronstointerneurons3. Interneuron• InterpretationofneuralmessagesintheCNSanddeterminationoftheappropriateresponse4. Efferentneuron(motor)• Efferentneuronstransmitresponsesignalsfrominterneuronstoeffectors5. Effector• Transmissionofneuralmessagetoeffectors(i.e.skeletalmuscles,glands,organs),where
appropriateactionoccurs
![Page 14: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/14.jpg)
ReflexArc
• Simplestnervecircuitpathway
• Allowsquickreactionusinganeuralcircuitthroughthespinalcord
• Governsanumberofcommonbodyresponses,especiallythosewhicharerepeated(e.g.,breathing,heartbeat,sweatglandsecretion,etc.)• Doesnot involvethebrain• However,interneuronsconnectedtoreflexcircuitsalsosendsignalstothebrain,makinganindividualawareofthestimulusthatcausedthereflex
![Page 15: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/15.jpg)
![Page 16: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/16.jpg)
Summary1. Howisthenervoussystemdivided?
• CNSandPNS
2. Whatarethecomponentsofaneuron?
• Dendriteà cellbodyà axon
3. Howdoesaneuralcircuitwork?
• Stimulià afferentneuronà interneuronà efferentneuronà response
4. Whatisareflexarc?
• Neuralpathwaythatcontrolsareflex(arapid,involuntaryresponsetoastimulus)
![Page 17: Lesson 2.14 - Nervous System (PPT)€¦ · Nervous System: complex network of nerves and cells that carry messages to and from the brain and spinal cord to the body 2 functional systems:](https://reader033.fdocuments.us/reader033/viewer/2022042311/5ed9c7793029ca4c5b53a85f/html5/thumbnails/17.jpg)
Homework
•Worksheetquestions