• Central Nervous Central Nervous SystemSystem (CNS) – (CNS) – – Brain and spinal cordBrain and spinal cord
• Peripheral Nervous Peripheral Nervous SystemSystem (PNS) – (PNS) – – Made up of nerves that Made up of nerves that
attach to CNSattach to CNS
Peripheral Nervous Peripheral Nervous SystemSystem
S ke le ta l
(S om atic)
S ym pathe tic P arasym pathe tic
A utonom ic
Periphera l Nervous S ystem
Functional Subdivisions Functional Subdivisions of the PNSof the PNS• PNS contains 2 PNS contains 2
functional functional subdivisionssubdivisions– Sensory Sensory
(afferent) (afferent) nervesnerves conduct conduct sensory impulses sensory impulses to CNS from to CNS from receptors in receptors in organs and tissuesorgans and tissues
– Motor (efferent) Motor (efferent) nervesnerves conduct conduct impulses away impulses away from CNS to from CNS to muscle effectors muscle effectors and glandsand glands
Subdivisions of Motor Subdivisions of Motor Division (PNS)Division (PNS)
• Somatic Nervous Somatic Nervous System System (SNS) –(SNS) –– Controls voluntary and Controls voluntary and
involuntary skeletal involuntary skeletal muscle contractionsmuscle contractions
– Involuntary skeletal Involuntary skeletal contraction – contraction – reflexreflex
– Single neuron systemSingle neuron system
• Autonomic Nervous Autonomic Nervous System System (ANS) –(ANS) –– Controls activity of Controls activity of
smooth and cardiac smooth and cardiac musclesmuscles
– 2 neuron system2 neuron system• 11stst: from CNS to ganglion: from CNS to ganglion• 22ndnd: from ganglion to : from ganglion to
effectoreffector
SubdivisioSubdivisions of ANSns of ANS
• Sympathetic Sympathetic divisiondivision – – – Fight or flightFight or flight
• ParasympatheParasympathetic divisiontic division – –– Regulates Regulates
resting functions resting functions • Ex., digesting Ex., digesting
foodfood
SympatheticSympathetic• “ “ Fight or flight” Fight or flight”
responseresponse• Release Release
adrenaline and adrenaline and noradrenaline noradrenaline
• Increases heart Increases heart rate and blood rate and blood pressurepressure
• Increases blood Increases blood flow to skeletal flow to skeletal musclesmuscles
• Inhibits digestive Inhibits digestive functionsfunctions
CENTRAL NERVOUS SYSTEMBrain
Spinalcord
Dilates pupil
Stimulates salivation
Relaxes bronchi
Accelerates heartbeat
Inhibits activity
Stimulates glucose
Secretion of adrenaline,nonadrenaline
Relaxes bladder
Stimulates ejaculationin male
Sympatheticganglia
Salivaryglands
Lungs
Heart
Stomach
Pancreas
Liver
Adrenalgland
Kidney
Inhibits
ParasympatheticParasympathetic• “ “ Rest and Rest and
digest ” digest ” systemsystem
• Calms body Calms body to conserve to conserve and maintain and maintain energyenergy
• Lowers Lowers heartbeat, heartbeat, breathing breathing rate, blood rate, blood pressurepressure
CENTRAL NERVOUS SYSTEMBrain
Spinalcord
Stimulates salivation
Constricts bronchi
Slows heartbeat
Stimulates activity
Contracts bladder
Stimulates erectionof sex organs
Stimulates gallbladder
Gallbladder
Contracts pupil
Summary of Summary of ANSANS differencesdifferencesAutonomic nervous system controls physiological arousal
Sympatheticdivision (arousing)
Parasympatheticdivision (calming)
Pupils dilate EYES Pupils contract
Decreases SALIVATION Increases
Perspires SKIN Dries
Increases RESPIRATION Decreases
Accelerates HEART Slows
Inhibits DIGESTION Activates
Secrete stresshormones
ADRENALGLANDS
Decrease secretionof stress hormones
• Made up primarily Made up primarily of 2 types of cells:of 2 types of cells:– NeuronsNeurons– Supporting cellsSupporting cells
•CNS - CNS - neuroglianeuroglia (glial cells) (glial cells)
– Astrocytes, Astrocytes, microglia, microglia, ependymal cells, ependymal cells, oligodendrocytesoligodendrocytes
•PNS – satellite PNS – satellite cells, Schwann cells, Schwann cellscells
NeuronsNeurons• Made up of a Made up of a cell cell bodiesbodies, , dendritesdendrites, and , and axonsaxons
• Cell bodyCell body (or (or somasoma))– Contains large nucleus Contains large nucleus
and and Nissl bodiesNissl bodies (Rough (Rough E.R.), primary site of E.R.), primary site of protein synthesisprotein synthesis
– Most located within CNS Most located within CNS where they are protected where they are protected by hard bones of skull by hard bones of skull and vertebral column and vertebral column
– Collection in CNS is called Collection in CNS is called ““nucleinuclei” whereas in PNS ” whereas in PNS they are called “they are called “gangliaganglia””
More on More on Neuron Neuron StructureStructure
• DendritesDendrites – Short, highly Short, highly
branched signal branched signal receptive regions of receptive regions of nerve cellnerve cell
– Convey incoming Convey incoming message toward the message toward the cell bodiescell bodies
• Each nerve cell Each nerve cell (neuron) has only (neuron) has only one one axonaxon– Impulse generating Impulse generating
and conducting and conducting region of neuronregion of neuron
Myelin Sheath of the Myelin Sheath of the AxonAxon
• Whitish, fatty protein Whitish, fatty protein layerlayer
• Serves to protect Serves to protect and electrically and electrically insulate axoninsulate axon
• Increases the speed Increases the speed of transmission of of transmission of nerve impulses (up nerve impulses (up to 150 times faster)to 150 times faster)
• Only associated with Only associated with axons, not dendritesaxons, not dendrites
REVIEW:REVIEW:Functional ClassificationFunctional Classification• Neurons are grouped according to the Neurons are grouped according to the
direction in which the nerve impulse direction in which the nerve impulse travels relative to the CNStravels relative to the CNS
• Based on this there are Based on this there are sensorysensory, , motormotor, and , and association neuronsassociation neurons– SensorySensory – transmit impulses from skin or – transmit impulses from skin or
other organs toward CNSother organs toward CNS– MotorMotor – carry impulses away from CNS to – carry impulses away from CNS to
effector organseffector organs– Association (interneurons)Association (interneurons) – lie between – lie between
motor and sensory neuronsmotor and sensory neurons
Neuroglia (CNS)Neuroglia (CNS)
• CNS has 4 different types of CNS has 4 different types of supporting cellssupporting cells ((neuroglianeuroglia))– Abundant and diverse Abundant and diverse – Limited knowledge of each function due to Limited knowledge of each function due to
difficulty in isolating individual cellsdifficulty in isolating individual cells• Ependymal cellsEpendymal cells
– Line central cavities of brain and spinal cordLine central cavities of brain and spinal cord– Beating of cilia help to circulate the Beating of cilia help to circulate the
cerebrospinal fluidcerebrospinal fluid (CSF) (CSF)– CSF: protection of brain and transport of vital CSF: protection of brain and transport of vital
nutrients and wastenutrients and waste• AstrocytesAstrocytes
– Attach neurons to capillaries, linking them to Attach neurons to capillaries, linking them to nutrient supplynutrient supply
Neuroglia CONT….Neuroglia CONT….•OligodendrocytesOligodendrocytes
– Branches wrap around neuron fibers, Branches wrap around neuron fibers, forming an insulating covering called a forming an insulating covering called a myelin sheathmyelin sheath
•MicrogliaMicroglia– Monitor health of nerve cellsMonitor health of nerve cells– If foreign invader detected or cell If foreign invader detected or cell
damaged, many microglia head to the damaged, many microglia head to the area, transform into macrophages, and area, transform into macrophages, and protect the CNS by phagocytizing the protect the CNS by phagocytizing the microorganisms or neuronal debrismicroorganisms or neuronal debris
Neuroglia (CNS)Neuroglia (CNS)
Label your Synapses Label your Synapses DiagramDiagram
• HINTS FOR YOU:HINTS FOR YOU:
= Sodium ions= Sodium ions
= Potassium ions= Potassium ions
= Calcium ions= Calcium ions
= synaptic vesicles w/ = synaptic vesicles w/ neurotransmittersneurotransmitters
= chemical gated channels= chemical gated channels
Use pages 392 and 406 in the AP book
Action potentialAction potential
• http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter14/animation__the_nerve_impulse.html
ANIMATION OF CHEMICAL ANIMATION OF CHEMICAL SYNAPSESSYNAPSES
• http://highered.mcgraw-hill.com/sites/0072495855/student_view0/chapter14/animation__chemical_synapse__quiz_1_.html
Animation of ENTIRE SYNAPTIC PROCESS with ACTION POTENTIAL
Sodium/Potassium PumpSodium/Potassium Pump
• http://highered.mcgraw-hill.com/http://highered.mcgraw-hill.com/sites/0072495855/student_view0/sites/0072495855/student_view0/chapter2/chapter2/animation__how_the_sodium_potasanimation__how_the_sodium_potassium_pump_works.htmlsium_pump_works.html
Action Potential GraphAction Potential Graph
•Know what happens at each Know what happens at each part of the graph with part of the graph with relationship to the pre-relationship to the pre-synaptic and post-synaptic synaptic and post-synaptic activities.activities.
•Look at the HANDOUT with Look at the HANDOUT with the graph!!the graph!!
• Also known as “Nerve Impulses”Also known as “Nerve Impulses”• Self-regenerating wave of Self-regenerating wave of electroelectrochemicalchemical
activity that allows neurons to carry a signal activity that allows neurons to carry a signal over a distance (“game of telephone”)over a distance (“game of telephone”)
• Pulse-like waves of voltage that Pulse-like waves of voltage that travel along several types of cell travel along several types of cell membranes membranes
• http://outreach.mcb.harvard.edu/animations/ http://outreach.mcb.harvard.edu/animations/ actionpotential.swfactionpotential.swf
• Initiation/Resting StageInitiation/Resting Stage::– Some Some K+K+ channels are channels are openopen: K+ diffusion : K+ diffusion
occurring occurring – Initiated by stimulus above a certain intensity Initiated by stimulus above a certain intensity
or or thresholdthreshold ((~~-70mV – -70mV – resting potentialresting potential))– Could be a pin prick, light, heat, sound or an Could be a pin prick, light, heat, sound or an
electrical disturbance in another part of the electrical disturbance in another part of the neuron (“telephone call”)neuron (“telephone call”)
– Electrical signal rises Electrical signal rises from changes in from changes in permeability of the permeability of the neuron’s axon membranes neuron’s axon membranes to specific ions ( to specific ions (Na+Na+ && K+K+))
Depolarization (Rising Phase)Depolarization (Rising Phase)• K+ ChannelK+ Channel gates are closedgates are closed• Stimulus causes gate in the Stimulus causes gate in the Na+ ChannelNa+ Channel to open to open• High concentration of Na+ outside, Na+ diffuses High concentration of Na+ outside, Na+ diffuses
intointo neuron neuron• Electrical potential changes to ~ +40 mV.Electrical potential changes to ~ +40 mV.
Repolarization (Falling Phase)Repolarization (Falling Phase)• Depolarization causes Depolarization causes K+ ChannelK+ Channel gate to gate to
immediately open & immediately open & Na+ ChannelNa+ Channel close close• K+ diffuses K+ diffuses out ofout of neuron neuron• Reestablishment of initial electrical potential of ~-Reestablishment of initial electrical potential of ~-
60 mV.60 mV.
Refractory Period (Recovery Phase)Refractory Period (Recovery Phase)• Na+ & K+ Channels cannot be opened by a stimulusNa+ & K+ Channels cannot be opened by a stimulus• Na+/K+ PumpNa+/K+ Pump actively (ATP) pumps actively (ATP) pumps Na+ outNa+ out of & of &
K+ intoK+ into neuron neuron• Reestablishment of ion distribution of resting neuronReestablishment of ion distribution of resting neuron• This AP acts as stimulus to neighboring proteins & This AP acts as stimulus to neighboring proteins &
initiates AP in another part of neuroninitiates AP in another part of neuron• Wave of APs travel from Wave of APs travel from
dendrites to axon terminalsdendrites to axon terminals• At axon terminal, At axon terminal, electrical electrical
impulseimpulse is converted to a is converted to a chemical signal (neurotransmitter)chemical signal (neurotransmitter)
http://bcs.whfreeman.com/thelifewire/content/chp44/4402002.html
Per. 2 start, Fri
Per. 4, WU go over handout
• Getting the message across Getting the message across (the synapse)? (the synapse)?– http://www.mind.ilstu.edu/curriculum/neurons_intro/neurons_intro.phphttp://www.mind.ilstu.edu/curriculum/neurons_intro/neurons_intro.php
– At axon terminal, chemical At axon terminal, chemical signal (NT) crosses synapse signal (NT) crosses synapse between adjacent neurons between adjacent neurons
• Starts AP on this neuronStarts AP on this neuron
– This activates This activates CaCa2+2+ channel channel to open to open• CaCa2+2+ diffuses diffuses intointo neuron neuron• Causes NT vesicles to move to end & fuse with cell Causes NT vesicles to move to end & fuse with cell
membranemembrane• Through Through exocytosisexocytosis, NTs are released into synapse, NTs are released into synapse
– NTs diffuse across synapse & bind to NT receptors on NTs diffuse across synapse & bind to NT receptors on another neuronanother neuron
• Causes Causes Na+ channelsNa+ channels to open & to open & AP is initiatedAP is initiated in next in next neuronneuron
• Information from one Information from one neuron flows to another neuron flows to another neuron across a neuron across a synapsesynapse……– a small gap separating a small gap separating
neurons that consists of: neurons that consists of: – a a presynaptic endingpresynaptic ending
that contains that contains neurotransmitters, neurotransmitters, mitochondria & other mitochondria & other organelles,organelles,
– a a postsynaptic endingpostsynaptic ending that contains receptor that contains receptor sites for neurotransmitters sites for neurotransmitters &&
– a a synaptic cleftsynaptic cleft or space or space between the presynaptic between the presynaptic & postsynaptic endings.& postsynaptic endings.
Let’s Review…Let’s Review…How do neurons communicate?How do neurons communicate?
• What is What is another name for the nerve impulseanother name for the nerve impulse that that travels from the axon hillock through the axon to the travels from the axon hillock through the axon to the axon terminal?axon terminal?
• What are the What are the 4 main phases4 main phases of an Action Potential? of an Action Potential?
• What happens in the What happens in the Rising PhaseRising Phase? ?
• Falling PhaseFalling Phase??
• Recovery PhaseRecovery Phase??
• Resting PotentialResting Potential??
• What What ionion entering the neuron entering the neuron instigates the movement of synaptic instigates the movement of synaptic vesicles to the cell membrane? vesicles to the cell membrane?
• What do the What do the vesicles releasevesicles release into into the synapse? the synapse?
• What happensWhat happens after the NTs are after the NTs are released into the synapse?released into the synapse?
Central Nervous SystemCentral Nervous System
•Brain and Brain and Spinal CordSpinal Cord
SpinalCord
Brain
• Average adult male’s brain weighs Average adult male’s brain weighs approximately 1.6 kg (~3.5 lbs)approximately 1.6 kg (~3.5 lbs)
• Average female’s: 1.42kgAverage female’s: 1.42kg• According to body weight, though…According to body weight, though…
they are relatively equal in sizethey are relatively equal in size
• Left & Right sides are Left & Right sides are separateseparate
• Corpus Callosum : major Corpus Callosum : major pathway between pathway between hemisphereshemispheres
• Some functions are Some functions are ‘lateralized’‘lateralized’– Language, numbers on leftLanguage, numbers on left– Color and music on rightColor and music on right
• Lateralization is never 100%Lateralization is never 100%
Brain has 2 HemispheresBrain has 2 Hemispheres
LeftHemisphere
Corpus CallosumRight
Hemisphere
Corpus CallosumCorpus Callosum• Major ( but not only) Major ( but not only)
pathway between sidespathway between sides• Connects comparable Connects comparable
structures on each sidestructures on each side• Permits data received on Permits data received on
one side to be processed one side to be processed in both hemispheresin both hemispheres
• Aids motor coordination Aids motor coordination of left and right side of left and right side
Corpus Callosum
Medial surface of right hemisphere
Contralateral Motor Contralateral Motor ControlControl
• Movements controlled Movements controlled by motor areaby motor area
• Right hemisphere Right hemisphere controls left side of controls left side of bodybody
• Left hemisphere Left hemisphere controls right sidecontrols right side
• Motor nerves cross Motor nerves cross sides in spinal cordsides in spinal cord
Somatosensory CortexMotor Cortex
Each hemisphere is Each hemisphere is divided into 4 lobes divided into 4 lobes
Frontal
Parietal
Occipital
Temporal
Cerebellum
• Cover and Cover and protect CNSprotect CNS
• Protect blood Protect blood vessels and vessels and enclose enclose venous venous sinusessinuses
• Contain Contain cerebrospinal cerebrospinal fluidfluid
• Form Form divisions divisions within the within the skullskull
Cerebral Cerebral White MatterWhite Matter
• Deep to the Deep to the gray gray matter matter of of cortex cortex
• Aids Aids communication communication between between cerebral cerebral areas and areas and between cerebral between cerebral cortex cortex and lower and lower CNS CNS
• Spinal cord has just the Spinal cord has just the opposite type of matteropposite type of matter
http://www.brainexplorer.org/brain-images/white_matter.jpg
FrontalLobe
Frontal LobeFrontal Lobe• Contains primary Contains primary
motor cortexmotor cortex
MotorCortexMotorCortexBroca’s
Area
MotorCortex
WorkingMemory
• No direct sensory No direct sensory inputinput
• Important planning Important planning and sequencing and sequencing areasareas
Broca’s area for Broca’s area for speechspeech
• Prefrontal area for Prefrontal area for working memoryworking memory
Occipital LobeOccipital Lobe
• Input from Optic Input from Optic nervenerve
• Contains primary Contains primary visual cortexvisual cortex– most is on surface most is on surface
inside central fissureinside central fissure
• Outputs to parietal Outputs to parietal and temporal lobesand temporal lobes
OccipitalLobe
VisualLobe
Temporal LobeTemporal Lobe• Inputs are auditory, Inputs are auditory,
visual patternsvisual patterns– speech recognitionspeech recognition– face recognitionface recognition– word recognitionword recognition– memory formationmemory formation
• Outputs to limbic Outputs to limbic System, basal System, basal Ganglia, and Ganglia, and brainstembrainstem
Contains primary auditory cortex
TemporalLobe
TemporalLobe
AuditoryCortex
ParietalLobe
SomatosensoryCortex
Parietal LobeParietal Lobe• Inputs from Inputs from
multiple sensesmultiple senses borders visual & auditory cortex
Outputs to Frontal lobe
hand-eye coordination
eye movements
attention
Regions & Regions & OrganizatioOrganizationn
• Cerebral Cerebral HemispheresHemispheres – –– Has outer cortex Has outer cortex
of gray matter of gray matter (neural bodies)(neural bodies)
• Diencephalon –Diencephalon –– Thalamus, Thalamus,
hypothalamus, hypothalamus, and epithalamusand epithalamus
• Brain StemBrain Stem – – – Midbrain, pons, Midbrain, pons,
medullamedulla• CerebellumCerebellum – –
– Has outer cortex Has outer cortex of gray matterof gray matter
Label the Label the worksheet on the worksheet on the brain!!brain!!•I will place the worksheet I will place the worksheet
under the under the document camera for document camera for you to view!!you to view!!
Cerebral HemispheresCerebral Hemispheres
• Approx. 83% of Approx. 83% of total brain masstotal brain mass
• Covered with Covered with elevations called elevations called gyrigyri and shallow and shallow grooves called grooves called sulcisulci
• Deeper grooves, Deeper grooves, called called fissuresfissures, , separate major separate major regions of the regions of the brainbrain
Cerebral CortexCerebral Cortex• It is the It is the gray mattergray matter of the cerebrum of the cerebrum• Enables us to perceive, communicate, Enables us to perceive, communicate,
remember, understand, appreciate, and remember, understand, appreciate, and initiate voluntary movementinitiate voluntary movement– It enables conscious behaviorIt enables conscious behavior
• Contains 3 functional areas:Contains 3 functional areas:– MotorMotor – control voluntary motor functions – control voluntary motor functions– SensorySensory – provide conscious awareness of – provide conscious awareness of
sensationsensation– AssociationAssociation – integrate diverse – integrate diverse
information for purposeful actioninformation for purposeful action
The Brain The Brain StemStem
• Includes:Includes:– MidbrainMidbrain– PonsPons– Medulla oblongataMedulla oblongata
• Structurally different Structurally different from brain because it from brain because it has deep has deep gray mattergray matter surrounded by surrounded by white matter (similar to spinal cord) white matter (similar to spinal cord)
• Coordinates head and eye movement when we Coordinates head and eye movement when we visually follow a moving object or see something out visually follow a moving object or see something out of corner of eyeof corner of eye
• Coordinates head reflex movement to unexpected Coordinates head reflex movement to unexpected auditory stimulusauditory stimulus
The DiencephalonThe Diencephalon• Surrounded by Surrounded by
the cerebral the cerebral hemisphereshemispheres
• Consists of 3 Consists of 3 bilaterally bilaterally symmetric symmetric structures:structures:– ThalamusThalamus– HypothalamusHypothalamus– EpithalamusEpithalamus
http://www.web-books.com/eLibrary/Medicine/Physiology/Nervous/diencephalon.jpg
The ThalamusThe Thalamus
•Egg-shaped Egg-shaped •Makes up 80% of Makes up 80% of
diencephalondiencephalon•Within the Within the
thalamus a thalamus a sorting-out and sorting-out and information information “editing” process “editing” process occursoccurs
The HypothalamusThe Hypothalamus• Caps the top of the brain stemCaps the top of the brain stem• Main visceral control center of the bodyMain visceral control center of the body• Vitally important to the homeostasis of the bodyVitally important to the homeostasis of the body• A few of its functions:A few of its functions:
– Regulates involuntary nervous system activities (blood Regulates involuntary nervous system activities (blood pressure, motility of digestive tract)pressure, motility of digestive tract)
– Perceives pleasure, fear, rage and sex drive (emotions)Perceives pleasure, fear, rage and sex drive (emotions)– Regulates body temp. by initiating Regulates body temp. by initiating – Regulates feelings of hunger and fullnessRegulates feelings of hunger and fullness– Regulates water balance and thirstRegulates water balance and thirst– Regulates sleep cycle in response to daylight-darkness Regulates sleep cycle in response to daylight-darkness
cues received by our eyescues received by our eyes– Controls endocrine system functioning – hormonal Controls endocrine system functioning – hormonal
balancebalance
EpithalamusEpithalamus
• Most dorsal portion of Most dorsal portion of the diencephalonthe diencephalon
• Forms roof of 3Forms roof of 3rdrd ventricleventricle
• Aids with sleep-wake Aids with sleep-wake cycle regulation cycle regulation ((pineal glandpineal gland))
• Helps with CSF Helps with CSF productionproduction
PonsPons• Helps to Helps to
maintain maintain normal normal rhythm of rhythm of breathingbreathing
• ““medulla”medulla”• Most inferior part Most inferior part
of the brain stemof the brain stem• Adjusts the force Adjusts the force
and rate of heart and rate of heart beat and depth of beat and depth of breathingbreathing
• Regulates Regulates vomiting, vomiting, hiccupping, hiccupping, swallowing, swallowing, coughing and coughing and sneezingsneezing
MedullaOblongata
The The CerebellumCerebellum
• Coordinate skeletal Coordinate skeletal muscle contractions muscle contractions needed for the needed for the smooth, coordinated smooth, coordinated movements of our movements of our daily lives daily lives – Ex., driving, Ex., driving,
typing, walkingtyping, walking• Cerebellar activity Cerebellar activity
occurs occurs subconsciouslysubconsciously
Cerebrospinal FluidCerebrospinal Fluid• Functions:Functions:
– Forms cushion for brain and other CNS organsForms cushion for brain and other CNS organs– Gives buoyancy to brain (which reduces weight by Gives buoyancy to brain (which reduces weight by
97%) to prevent brain from crushing under own 97%) to prevent brain from crushing under own weightweight
– Also helps blood in providing brain with nourishmentAlso helps blood in providing brain with nourishment
• Fun Fact:Fun Fact:– Average adult brain contains 150 ml and is replaced Average adult brain contains 150 ml and is replaced
every 3-4 hoursevery 3-4 hours
• Application:Application:– If CSF becomes obstructed, can cause condition If CSF becomes obstructed, can cause condition
called called hydrocephalushydrocephalus • Enlargement of the head in babies and brain damage in Enlargement of the head in babies and brain damage in
adultsadults
Looks Can Be DeceivingvWhat are these kinds of pictures called?
vWhat do these do to neuron communication within our Nervous System?
The The Dancing Dancing GirlGirl
• Look at the Look at the Dancer…Dancer…– Which way is she Which way is she
turning?turning?• ClockwiseClockwise? ? • Counter-clockwiseCounter-clockwise??
– Now stare at her Now stare at her bottom foot & squint bottom foot & squint your eyes…your eyes…• Does she start turning Does she start turning
the the other directionother direction??
Get lost in Get lost in the circlesthe circles• What happens What happens
when you focus when you focus on the on the center of center of a circlea circle??
Anatomy WARM-UPAnatomy WARM-UP• Read the article about Phineas Gage Read the article about Phineas Gage
then answer the following questions: then answer the following questions:
• What was Phineas’ occupation?What was Phineas’ occupation?• Why is the Phineas Gage story Why is the Phineas Gage story
so popular among medical so popular among medical science?science?
• Was there a change in Was there a change in Gage after the accident?Gage after the accident?
• Where can you go and view Where can you go and view Gage’s skull? Gage’s skull?
33rdrd qtr; week 5; day 2 qtr; week 5; day 2
• On a separate paper, write your On a separate paper, write your thoughts about this picture…thoughts about this picture…
• Your reactionsYour reactions• What do you think caused this What do you think caused this
situation?situation?– Based on what you know,Based on what you know,
• what kind of what kind of repercussionsrepercussions would would this accident have on the nervous this accident have on the nervous system?system?
– Now read the following story of Now read the following story of Phineas Gages’ tragic accident…Phineas Gages’ tragic accident…
– Write about your reactions to the Write about your reactions to the accidentaccident
• What What surprisedsurprised you about any info you about any info learned?learned?
• What kinds of things does the pre-What kinds of things does the pre-frontal cortex (lobe)frontal cortex (lobe) regulate? regulate?
VisionVision• PhotoreceptorsPhotoreceptors
are the visual are the visual receptor cellsreceptor cells
• Adult eye Adult eye averages 1 inch in averages 1 inch in diameterdiameter
• Accessory Accessory structures of the structures of the eye protect the eye protect the eye or aid in its eye or aid in its functioningfunctioning
Accessory StructuresAccessory Structures
• EyebrowsEyebrows• EyelidsEyelids• ConjunctivaConjunctiva• Lacrimal Lacrimal
apparatusapparatus• Extrinsic Eye Extrinsic Eye
musclesmuscles
Lacrimal ApparatusLacrimal Apparatus• Consists of the Consists of the lacrimal lacrimal
glandgland and and lacrimal lacrimal ductsducts
• Lacrimal gland releases Lacrimal gland releases fluid that contains mucus, fluid that contains mucus, antibodies, and lysozyme antibodies, and lysozyme (a bacteria-destroying (a bacteria-destroying enzyme)enzyme)
• Lacrimal gland is located Lacrimal gland is located superior and lateral to the superior and lateral to the eyeeye– It releases fluid, which is It releases fluid, which is
spread over eye by blinking, spread over eye by blinking, and drains via the medial and drains via the medial lacrimal canalslacrimal canals
PAGE 555 in AP book
Eyebrows and EyelidsEyebrows and Eyelids• EyebrowsEyebrows overlie the overlie the
supraorbial margins of the skullsupraorbial margins of the skull• They shade the eyes from They shade the eyes from
sunlight and prevent sunlight and prevent perspiration from entering the perspiration from entering the eyeseyes
• EyelidsEyelids cover the eye when cover the eye when the orbicularis oculi contractthe orbicularis oculi contract
• This occurs (blinking) every This occurs (blinking) every three to seven seconds to three to seven seconds to prevent desiccation of the eyesprevent desiccation of the eyes–EyelashesEyelashes (palpabrae)
are richly innervated, are richly innervated, so anything that so anything that touches them, including touches them, including a puff of air, triggers a puff of air, triggers reflex blinkingreflex blinking
Structure of the EyeballStructure of the Eyeball• Made up of three layers called tunics: fibrous (1), vascular (2) and Made up of three layers called tunics: fibrous (1), vascular (2) and
sensory (3)sensory (3)• Fibrous tunic is the outermost coat of the eyeFibrous tunic is the outermost coat of the eye• It is divided into two major regions: the cornea and the scleraIt is divided into two major regions: the cornea and the sclera• The sclera (tough connective tissue) is the “white of the eye” and The sclera (tough connective tissue) is the “white of the eye” and
functions to protect and shape the eyeballfunctions to protect and shape the eyeball• Also serves as sturdy anchoring point for Also serves as sturdy anchoring point for
extrinsic eye musculature extrinsic eye musculature
• PLEASE LABEL your PLEASE LABEL your wksht with color coding of wksht with color coding of your 3 tunics your 3 tunics
3
Iris Iris ((Vascular Vascular TunicTunic))
• Though it seems to appear Though it seems to appear in many colors (Iris means in many colors (Iris means rainbow), it actually only rainbow), it actually only contains brown pigmentcontains brown pigment
• When an iris contains a lot When an iris contains a lot of pigment, the eyes appear of pigment, the eyes appear brown or blackbrown or black
• If the amount of pigment is If the amount of pigment is small, the short small, the short wavelengths of light are wavelengths of light are scattered from the scattered from the unpigmented parts of the unpigmented parts of the iris, and eyes appear blue, iris, and eyes appear blue, green, or graygreen, or gray
• Why, then, do newborn Why, then, do newborn babies often appear to have babies often appear to have gray or blue eyes?gray or blue eyes?
The Sensory TunicThe Sensory Tunic• Contains the Contains the lens lens (hard (hard
disc) which allows an image disc) which allows an image that is upside down and that is upside down and backwards.backwards.
• This is the deepest layer This is the deepest layer and also has pigmented and also has pigmented cells that absorb lightcells that absorb light
• Also stores Vitamin A, Also stores Vitamin A, which is needed by the which is needed by the Photoreceptor cellsPhotoreceptor cells
• The retina contains millions The retina contains millions of photoreceptors known as of photoreceptors known as cones and rodscones and rods
Lens
CHECK YOUR LABELS!!!
ConjunctivaConjunctiva• A transparent mucous A transparent mucous
membrane that lines the membrane that lines the eyelids and reflects over the eyelids and reflects over the surface of the eyeballsurface of the eyeball
• It functions to lubricate the It functions to lubricate the eye and to prevent invasion eye and to prevent invasion to the posterior portion of to the posterior portion of the eyethe eye
• Conjunctivitis is an Conjunctivitis is an inflammation of the inflammation of the conjunctiva; Pinkeye is a conjunctiva; Pinkeye is a type of conjunctivitis caused type of conjunctivitis caused by bacteria or virusby bacteria or virus
More on the EyeMore on the Eye
• Cornea is lined with pain Cornea is lined with pain fibers (which is why contacts fibers (which is why contacts can be so tough to can be so tough to adjust to)adjust to)
• When cornea is touched, When cornea is touched, reflex blinking and increased reflex blinking and increased lacrimal fluid secretion occurlacrimal fluid secretion occur
• Since cornea has no blood supply it is the only Since cornea has no blood supply it is the only tissue that can be transplanted with very little tissue that can be transplanted with very little fear of rejection (does not have contact with fear of rejection (does not have contact with immune system)immune system)
Internal Internal ChambersChambers
• Filled with Filled with aqueous humoraqueous humor which is produced in the which is produced in the posterior chamber and posterior chamber and drains from the anterior drains from the anterior chamberchamber
• If this drainage is blocked, If this drainage is blocked, pressure within the eye may pressure within the eye may increase and cause increase and cause compression of the retina compression of the retina and optic nerve-a condition and optic nerve-a condition called called glaucomaglaucoma
• Exam to diagnose is simple…Exam to diagnose is simple…a puff of air at the sclera will a puff of air at the sclera will produce a measurable produce a measurable amount of deformationamount of deformation
Colorblind TestsColorblind Tests
• http://www.toledo-bend.com/http://www.toledo-bend.com/colorblind/Ishihara.htmlcolorblind/Ishihara.html
• http://colorvisiontesting.com/http://colorvisiontesting.com/onlineonline%20test.htm#demonstration%20test.htm#demonstration%20card%20card
ENDOCRINE SYSTEMENDOCRINE SYSTEM
•Responsible for sending Responsible for sending messages to target organs messages to target organs by secreting hormonesby secreting hormones
•Moves slower than the Moves slower than the Nervous systemNervous system
•
ENDOCRINE SYSTEMENDOCRINE SYSTEM• Please label all Please label all
of the glands of the glands on your wksht on your wksht and explain and explain what hormone what hormone is secreted is secreted from each of from each of them.them.
• Use pages 591-692Use pages 591-692 in the Anatomy in the Anatomy book!book!
Yes, you will need to identify what the hormone does for the body…MAKE IT BRIEF!!
THE ENDTHE END
The EarThe Ear
• Divided into three Divided into three major regions:major regions:
• Inner earInner ear• Middle earMiddle ear• Outer earOuter ear
•
LABEL YOUR WORKSHEET Page 573 in AP book
Outer EarOuter Ear• AuricleAuricle = the ear = the ear• made up of the made up of the helixhelix
(rigid portion) and(rigid portion) and lobulelobule (no cartilage) (no cartilage)
• directs sound waves directs sound waves into into auditory canalauditory canal
• canal is short (2.5 cm) canal is short (2.5 cm) and curved and and curved and extends to the extends to the tympanic membranetympanic membrane
• Canal is lined with Canal is lined with hairs, sebaceous hairs, sebaceous glands, and aprocrine glands, and aprocrine sweat glands called sweat glands called ceruminous glandsceruminous glands
Middle EarMiddle Ear• Small, air-filled Small, air-filled
cavity within the cavity within the petrous portion of petrous portion of temporal bonetemporal bone
• Eustachian tubeEustachian tube links middle ear to links middle ear to superiormost part of superiormost part of the throatthe throat– Normally this is Normally this is
closed, but yawning closed, but yawning and swallowing opens and swallowing opens this tube briefly to this tube briefly to equalize pressureequalize pressure
• Contains the three smallest bones Contains the three smallest bones in the body: the in the body: the ossiclesossicles
• Malleus (hammer)Malleus (hammer) – secured to – secured to the tympanic membranethe tympanic membrane
• Incus (anvil)- Incus (anvil)- connects other connects other bonesbones
• Stapes (stirrup)Stapes (stirrup) – connects to the – connects to the inner ear (via the oval window)inner ear (via the oval window)
• Tensor tympaniTensor tympani muscle attaches muscle attaches the auditory tube. The the auditory tube. The stapediusstapedius muscle runs from the wall of the muscle runs from the wall of the middle ear cavity and inserts into middle ear cavity and inserts into the stapesthe stapes
• These two muscles work together These two muscles work together to prevent damage to the inner ear to prevent damage to the inner ear under extremely loud conditionsunder extremely loud conditions
Inner EarInner Ear• Located deep Located deep
within the within the temporal bone temporal bone and posterior to and posterior to the eye socketthe eye socket
• Made up of the Made up of the vestibule, vestibule, cochlea, and cochlea, and semicircular semicircular canalscanals
VestibuleVestibule• Central egg-shaped Central egg-shaped
cavity that medially cavity that medially borders the middle earborders the middle ear
• Has oval window in its Has oval window in its lateral walllateral wall
• Contains perilymph Contains perilymph (similar to CSF)(similar to CSF)
• Houses equilibrium Houses equilibrium Sensors called Sensors called maculae that respond maculae that respond to the pull of gravity to the pull of gravity and report changes of and report changes of head positionhead position
Semicircular CanalsSemicircular Canals
• Made up of an Made up of an anterior, anterior, posterior, and posterior, and lateral canallateral canal
• Also have Also have receptors to help receptors to help with equilibriumwith equilibrium
CochleaCochlea• About half the size of About half the size of
a peaa pea• Contains three hollow Contains three hollow
cavities: Scala cavities: Scala vestibuli(terminates at vestibuli(terminates at oval window), cochlear oval window), cochlear duct, scala tympani duct, scala tympani (terminates at round (terminates at round window)window)
• Cochlear duct contains Cochlear duct contains spiral organ of Corti, spiral organ of Corti, which is the receptor which is the receptor organ for hearingorgan for hearing
HearingHearing
• Sounds set up vibrations in air that beat Sounds set up vibrations in air that beat against the ear drumagainst the ear drum
• This pushes the ossicles that press fluid This pushes the ossicles that press fluid in the inner ear against membranesin the inner ear against membranes
• This pressure on the membranes pulls This pressure on the membranes pulls on tiny hair cells that stimulate nearby on tiny hair cells that stimulate nearby neurons that give rise to impulses that neurons that give rise to impulses that travels to the brain, where they are travels to the brain, where they are interpretedinterpreted
Hair Cells in the Hair Cells in the Spiral Organ of Spiral Organ of CortiCorti
• Lining the organ of Lining the organ of Corti you find Corti you find roughly 16,000 roughly 16,000 hearing receptor hearing receptor cells called cochlear cells called cochlear hair cells sandwiched hair cells sandwiched between basilar between basilar membrane and membrane and tectorial membranetectorial membrane
DeafnessDeafness• Two types: conduction or sensorineuralTwo types: conduction or sensorineural• Conduction deafness – occurs when something Conduction deafness – occurs when something
interferes with conduction of sound vibrations interferes with conduction of sound vibrations to the fluids of the innner earto the fluids of the innner ear
• Sensorineural deafness – results from damage Sensorineural deafness – results from damage to neural structures at any point in the hearing to neural structures at any point in the hearing pathwaypathway– This typically result from the gradual loss of the This typically result from the gradual loss of the
hearing receptor cells:hearing receptor cells:• Throughout lifeThroughout life• Single explosively loud noiseSingle explosively loud noise• Prolonged exposure to high-intensity sounds, which cause Prolonged exposure to high-intensity sounds, which cause
these cells to stiffen these cells to stiffen (IPODs)(IPODs)