The document discusses the autonomic nervous system, which has two divisions - the sympathetic and parasympathetic systems. The sympathetic system prepares the body for fight or flight by increasing heart rate and blood pressure. The parasympathetic system then takes over once the stressor is gone, calming the body down.

1. AUTONOMICAUTONOMIC
NERVOUS SYSTEMNERVOUS SYSTEM
SYMPATHETIC ANDSYMPATHETIC AND
PARASYMPATHETIC SYSYTEMPARASYMPATHETIC SYSYTEM

2. DIVISIONSDIVISIONS
 Two divisionsTwo divisions
CNS (CENTRAL NERVOUS SYSTEM)CNS (CENTRAL NERVOUS SYSTEM)
 PNS (PERIPHERAL NERVOUSPNS (PERIPHERAL NERVOUS
SYSTEM)SYSTEM)

3. CENTRAL NERVOUS SYSTEMCENTRAL NERVOUS SYSTEM
 Central nervous systemCentral nervous system
 Receives and processesReceives and processes
 informationinformation
 Initiates actionsInitiates actions
 PARTSPARTS
 Brain, spinal cordBrain, spinal cord
 and tractsand tracts

4. CENTRAL NERVOUS SYSTEMCENTRAL NERVOUS SYSTEM
 Tracts are bundles of axons formingTracts are bundles of axons forming
a pathwaya pathway
 Nerves are bundles of axons ofNerves are bundles of axons of
sensory or motor neurons existingsensory or motor neurons existing
outside of the CNSoutside of the CNS

5. BRAINBRAIN
 Receives andReceives and
 processes sensory informationprocesses sensory information
 Initiates responsesInitiates responses
 Stores memoriesStores memories
 Generates thoughts and emotionsGenerates thoughts and emotions

7. SPINAL CORDSPINAL CORD
 Conducts signals to and from theConducts signals to and from the
brainbrain
 Controls reflex activitiesControls reflex activities
 Generates rhythmic components of
locomotor movements

8. SPINAL CORD

9. Peripheral nervous systemPeripheral nervous system
 Sensory neurons, ganglia and nervesSensory neurons, ganglia and nerves
 Transmits signals between CNS andTransmits signals between CNS and
rest of the bodyrest of the body
 Motor neuronsMotor neurons
 Sensory neuronsSensory neurons

10. MOTOR NEURONSMOTOR NEURONS
 Somatic nervous systemSomatic nervous system
 Controls voluntary movementsControls voluntary movements
 Autonomic nervous systemAutonomic nervous system
 Controls involuntary responsesControls involuntary responses

11. AUTONOMOC NERVOUSAUTONOMOC NERVOUS
SYSTEMSYSTEM
 Sympathetic nervous systemSympathetic nervous system
 Parasympathetic nervous systemParasympathetic nervous system
 However, the autonomic motorHowever, the autonomic motor
neuron only modifies the activity ofneuron only modifies the activity of
the visceral muscle that it acts onthe visceral muscle that it acts on

12. AUTONOMIOC NERVOUSAUTONOMIOC NERVOUS
SYSTEMSYSTEM
 Example:Example:
 Heart continues to beat, muscles of intestinalHeart continues to beat, muscles of intestinal
walls continue to contract even if all nerves towalls continue to contract even if all nerves to
these organs are destroyed.these organs are destroyed.

13. STRUCTURAL AND FUNCTIONSTRUCTURAL AND FUNCTION
 1. Cell body (soma)1. Cell body (soma)
contains the nucleuscontains the nucleus
(containing the genetic(containing the genetic
info) and other thingsinfo) and other things
found in most cells. Itfound in most cells. It
also producesalso produces
neurotransmitter whichneurotransmitter which
are stored in synapticare stored in synaptic
vesicles.vesicles.
 2. Dendrites - receives2. Dendrites - receives
incoming signals fromincoming signals from
other neurons. Theyother neurons. They
look like plant roots.look like plant roots.

14. REFLEXES
 Involves an automatic response to stimuli.
 The sensory neuron is stimulated by stimuli, send
impulse to spinal cord.
 An interneuron in the spinal cord simultaneously
sends impulse to:
 1. Motor neuron in the finger
 2. To the brain

15. REFLEXES
 Consequently, you react before the message
reaches the brain. Thus you feel no pain as you
react, but feel it afterwards.

16. AXONSAXONS
 A single tube like fiber that is thickerA single tube like fiber that is thicker
and longer than Dendrites.and longer than Dendrites.
 It is used by the neuron to transmitIt is used by the neuron to transmit
an electrical impulse to otheran electrical impulse to other
neurons.neurons.
 They may be tiny or up to a meter inThey may be tiny or up to a meter in
length.length.

17. BRAINBRAIN
 CraniumCranium
 Part of the skullPart of the skull
 Protects the brain and neural archesProtects the brain and neural arches
 Triple layer of meningesTriple layer of meninges
 The membranes that cover the brainThe membranes that cover the brain
and spinal cordand spinal cord

18. MENINGES

19. MENINGES
 Meninges are filled with csf
 Primary function of csf and
memninges
 To protect the cns

20. CSFCSF
 Between these cerebrospinal fluidBetween these cerebrospinal fluid
 Similar ion composition to bloodSimilar ion composition to blood
plasmaplasma
 Bathes the neurons of brain and spinlBathes the neurons of brain and spinl
cordcord

22. CNSCNS
 Spinal cord has central canalSpinal cord has central canal
 Brain ha many cavitiesBrain ha many cavities

23. CNSCNS
 Provision of cushion against bumpsProvision of cushion against bumps
and joltand jolt
 Vertebrae of vertebral columnVertebrae of vertebral column
protects the spinal cordprotects the spinal cord
 Brain and spinal cord are hollowBrain and spinal cord are hollow

24. FORE BRAINFORE BRAIN
 ThalamusThalamus
 The limbic systemThe limbic system
 CerebrumCerebrum

26. THALAMUSTHALAMUS
 Carries sensory information to limbicCarries sensory information to limbic
system and cerebrumsystem and cerebrum
 Sensory inputs from auditory andSensory inputs from auditory and
visual pathways from skin and withinvisual pathways from skin and within
the bodythe body
 The relay center of the brainThe relay center of the brain

27. THE LIMBIC SYSTEMTHE LIMBIC SYSTEM
 Between the thalamus and cerebrumBetween the thalamus and cerebrum
 Drive basic and primitive emotionsDrive basic and primitive emotions
 Drives, behavioursDrives, behaviours
 FearFear
 RageRage
 TranquilityTranquility
 HungerHunger

29. THE LIMBIC SYSTEMTHE LIMBIC SYSTEM
 ThirstThirst
 PleasurePleasure
 Sexual responsesSexual responses
 Formation of memoriesFormation of memories

30. THE LIMBIC SYSTEMTHE LIMBIC SYSTEM
 HypothalamusHypothalamus
 AmydalaAmydala
 HippocampusHippocampus
 Nearby regions of cerebrumNearby regions of cerebrum


31. THE LIMBIC SYSTEMTHE LIMBIC SYSTEM
 Main purpose is to control theMain purpose is to control the
internal environment of the body. Itinternal environment of the body. It
does this bydoes this by
 Influences the pituitary gland - whichInfluences the pituitary gland - which
releases hormonesreleases hormones
 Influences drive states such as thirstInfluences drive states such as thirst
and hungerand hunger
 influences activity of the Autonomicinfluences activity of the Autonomic
NSNS
 Involved in emotionsInvolved in emotions

32. HYPOTHALAMUSHYPOTHALAMUS
 Production of hormonesProduction of hormones
 Neural connectionsNeural connections
 Major coordinating centerMajor coordinating center
 Body temperatureBody temperature
 HungerHunger
 The menstrual cycleThe menstrual cycle
 Water balanceWater balance
 Sleep awake cyclesSleep awake cycles

33. AMYDALAAMYDALA
 Cluster of neuronsCluster of neurons
 Sensation of pleasureSensation of pleasure
Sensation of punishmentSensation of punishment
Sensation of sexual arousalSensation of sexual arousal
Feelings of fearFeelings of fear
RageRage

34. HIPPOCAMPUSHIPPOCAMPUS
 Formation of long term memoryFormation of long term memory
 Required for learningRequired for learning

35. CEREBRUMCEREBRUM
 Largest part of the brainLargest part of the brain
 Divided into two halvesDivided into two halves
 Cerebral hemispheresCerebral hemispheres
 Two halve communicate to eachTwo halve communicate to each
other by means of large band ofother by means of large band of
axonsaxons
 Corpus callosumCorpus callosum

37. CORPUS CALLOSUMCORPUS CALLOSUM
 Tens of billions of neurons areTens of billions of neurons are
presentpresent

39. SYMPATHETIC SYSTEMSYMPATHETIC SYSTEM
 This makes you alert and ready forThis makes you alert and ready for
actionaction
Relaxes the bladderRelaxes the bladder
Stimulates adrenal glandsStimulates adrenal glands
Cools the body with perspirationCools the body with perspiration

40. SYMPATHETIC SYSTEMSYMPATHETIC SYSTEM
Arousal for defensive actionArousal for defensive action
Prepares body for fight or flight),Prepares body for fight or flight),
Increases heart rateIncreases heart rate
Blood pressureBlood pressure
Increases blood sugarIncreases blood sugar
Dilates arteries to increase blood flow toDilates arteries to increase blood flow to
musclesmuscles

42. Parasympathetic SYSTEMParasympathetic SYSTEM
 When the stressor is over, this takesWhen the stressor is over, this takes
over.over.
 Calming, conserves energyCalming, conserves energy
 Produces the opposite effectProduces the opposite effect
Decreases heart rateDecreases heart rate