Chap 3 - Nervous System.txt

  1. What is the nervous system?
    Body's principal control system, regulates all bodily functions via electrical impulses transmitted thru nerves
  2. Nervous system is broken down into '2' divisions
    • Central Nervous System (CNS)
    • Peripheral Nervous System (PNS)
  3. What is the central nervous system?
    Consists of the brain and the spinal cord
  4. Peripheral Nervous System breakdown
    Image Upload 1
  5. What is the Peripheral Nervous System?
    Composed of the cranial nerves from the brain and peripheral nerves from the spinal cord

    Subdivision are: somatic nervous system (aka. voluntary) & automatic nervous system (aka involuntary)
  6. What are the '4' categories of peripheral nerves?
    • Somatic sensory
    • Somatic motor
    • Visceral (automatic) sensory
    • Visceral (automatic) motor
  7. What is the somatic sensory nerve?
    Afferent nerves that transmit sensations such as touch, pressure, pain, temperature, & position
  8. What is the somatic motor nerve?
    Efferent fibers that carry impulses to the skeletal (voluntary) muscles
  9. What is the visceral (automatic) sensory nerve?
    Afferent tracts that transmit sensations from the visceral organs.

    Sensation such as need to pee & take a crap
  10. What is the visceral (automatic) motor nerve?
    Efferent fibers that exit the CNS & branch to supply nerves to the cardic muscle & smooth muscle of the viscera (organs) & glands
  11. What is the Somatic (Voluntary) Nervous System?
    Governs voluntary functions (those we consciously control)

    ie. control of movement & skeletal muscles

    Subdivision of the peripheral nervous system
  12. What is the Automatic (Involuntary) Nervous System?
    Controls involuntary bodily functions (ie. smooth muscle, cardiac muscle, glands)

    Subdivision of the peripheral nervous system

    Divided into: sympathetic nervous system & parasympathetic nervous system
  13. What is autonomic ganglia?
    Groups of autonomic nerve cells located outside the CNS
  14. What are the preganglionic nerves?
    Nerve fibers that extend from the CNS to tht autonomic ganglia
  15. What is the postganglionic nerves?
    Nerve fibers that extend from the autonomic ganglia to the target tissues
  16. What is the Sympathetic Nervous System?
    Division of the automatic nervous system

    Prepares the body for 'fight or flight'

    • Body reacts by:
    • * ^ HR
    • * Bronchioles dilate
    • * Pupils dilate
    • * Decrease organ & digestion activity
    • * Vasocontriction

    Nerves: thoracic & lumbar regions

    Adrenal medulla gland is responsible for the release of the hormones

    • Neurotransmitters: epinephrine (80%)
    • norepinephrine (20%)
  17. What are the '2' types of sympathetic ganglia?
    • Sympathetic chain ganglia
    • Collateral ganglia
  18. What are the effects when the sympathtic chain ganglia is stimulated?
    • ^ BP
    • Stimulation of secretion by sweat glands
    • Constriction of blood vessels in the skin
    • ^ in blood flow to skeletal muscles
    • ^ HR
    • ^ force of cardiac contraction
    • Bronchodilation
    • Stimulation of energy production
  19. What are the effects when the collateral ganglia is stimulated?
    • Reduction in blood flow to abdominal organs
    • Decreased digestive activity
    • Relaxation of smooth muscle in the wall of the urinary bladder
    • Release of glucose stores from the liver
  20. What are the '2' types of sympathetic receptors?
    • Adrenergic receptors
    • Dompaminergic receptors
  21. What are the '4' types of adrenergic receptors?
    • * Alpha1
    • * Apha2

    • * Beta1
    • * Beta2
  22. What are the effects of the apha1 receptors?
    • Peripheral vasoconstriction
    • Mild bronchoconstriction
    • Stimulation of metabolism
  23. What are the effects of the alpha2 receptors?
    Prevent overrelease of norepinephrine
  24. What are the effects of beta1 receptors?
    • ^ HR
    • ^ cardiac contractile force
    • Cardiac automaticity & conduction
  25. What are the effects of beta2 receptors?
    • Vasodilation
    • Bronchodilation
  26. What are the effects of dopaminergic receptors?
    Dilation of renal, coronary & cerebral arteries
  27. What is the parasympathetic nervous system?
    Division of the automatic nervous system

    Controls the 'feed or breed' or rest & regenerative

    Arises from the brainstem & sacral segments of the spinal cord

    • Body actions:
    • * decreased HR & cardiac contractile force
    • * bronchioles constrict
    • * Pupils constrict
    • * sexual stimulation
    • * ^ digestive activity

    Nerves: sacral region & cranial nerves (vagus nerve)

    Neurotransmitters: Acetylcholine
  28. What are the '4' cranial nerves that carry parasympathetic fibers?
    • III: oculomotor nerve
    • VII: facial nerve
    • IX: glossopharyngeal nerve
    • X: vagus nerve
  29. What are the '2' types of acetylcholinesterase (ACh)?
    • Nicotinic
    • Muscarinie
  30. What are the '2' nicotinic receptors called?
    NicotinicN (neuron): found in autonomic ganglia; parasympathetic & sympathetic systems

    NicotinicM (muscle): found at the neuromuscular junction, initiate muscular contraction; somatic nervous system
  31. What are the muscarinic receptors responsible for?
    promoting the parasympathetic response
  32. What is a neuron?
    • * nerve cell
    • * fundamental component of nervous system
  33. Anatomy of the neuron
    Image Upload 2
  34. Parts of the Neuron & their functions?
    • * Soma: cell body, contains the nucleus, mitochondria & ribosomes
    • * Dendrites: transmit electrical impulses to cell body
    • * Axons: transmit electrical impulses away from the cell body
    • * Synaptic terminals: affect another neuron or effector
  35. Neuron in resting state....
    • '+' charged on outside
    • '-' charged on the inside
  36. Neuron electrically stimulated....
    • NA rapidly surges into the cell
    • K rapidly leaves the cell
    • thus depolarization of the neuron
  37. What is a neurotransmitter?
    substance released from axon terminal of neuron on excitation travels across the synpatic cleft to either excite or inhibit the target cell

    examples: acetylcholine, norepinephrine, dopamine
  38. Where does the brain lie?
    Within the cranium vault protected by the skull
  39. What bones make up the cranium?
    • frontal bone
    • occipital bone
    • parietal bones
    • temporal bones
    • sphenoid bones
    • ethmoid bones
  40. Bones of the human skull
    Image Upload 3
  41. What are the meninges?
    protective membranes that cover the entire CNS
  42. There are '3' layers of meninges...
    • Dura Mater: durable outermost layer
    • Arachnoid Membrane: weblike structure middle layer
    • Pia Mater: innermost layer
  43. What is the subarachoid space?
    space b/t the pia mater & anachnoid membrane
  44. What is the subdural space?
    space b/t the dura mater & arachnoid membrane
  45. What is the space outside the dura mater called?
    Epidural space
  46. What is cerebrospinal fluid (CSF)? Where is it found?
    • Its a watery clear fluid
    • brain & spinal cord are bathed in it
  47. What are the '6' parts of the brain?
    • Cerebrum
    • Diencephalon (thalmus & hypothalmus)
    • Mesencephalon (midbrain)
    • Pons
    • Medulla Oblongata
    • Cerebellum
  48. What '2' areas of the brain make up the forebrain?
    • Cerebrum
    • Diencephalon
  49. What is Cerebrum?
    • Located in the anterior & middle are of the cranium
    • Contains '2' hemispheres which are joined together by the corpus callosum
    • Responsible for: sensory & motor actions, intelligence, learning, analysis, memory, language
  50. What functions do the frontal areas of the Cerebrum control?
    • personality
    • motor
  51. What is the temporal lobe of the cerebrum responsible for?
  52. What is the occipital cortex of the cerebrum responsible for?
  53. What are the parietal lobes of the cerebrum responsible for?
  54. What is the Diencephalon?
    • covered by the cerebrum
    • aka. interbrain
    • thalamus, hypothalamus & limbic system
    • Responsible for: involuntary actions, temperature regulation, sleep, water balance, stress response & emotions
    • Major role: regulating autonomatic nervous system
  55. What areas of the brain make up the brainstem?
    • Mesencephalon (midbrain)
    • Pons
    • Medulla Oblongata
  56. What areas of the brain make up the hindbrain?
    • Brainstem
    • Cerebellum
  57. What is the mesencephalon?
    • aka. midbrain
    • Located b/t the diencephalon & the pons
    • Responsible for: motor coordination & eye movement
  58. What is the pons?
    • Located b/t midbrain & medulla oblongata
    • Contains connections b/t the brain & spinal cord
  59. What is the medulla oblongata?
    • Located b/t the pons & the spinal cord
    • Marks the division b/t the spinal cord & brain
    • Responsible for: controlling respirations, cardiac activity, vasomotor activity
  60. What is the cerebellum?
    • Located in the posterior fossa
    • Consists of '2' hemispheres
    • Responsible for: fine motor movement, posture, equilibrium, muscle tone, balance & coordination
  61. What is the Reticular Activating System (RAS)?
    • Operates in the lateral portion of the medulla, pons & midbrain
    • Sends impulses to & receives impulses from cerebral cortex
    • Responsible for: maintaining consciousness & ability to respond to stimuli
  62. What '2' systems supply blood to the brain?
    • Carotid system is anterior
    • Vertebrobasilar system is posterior

    Venous drainage thru venous sinuses & internal jugular veins
  63. Lobes of the brain
    Image Upload 4
  64. Parts of the Brain
    Image Upload 5
  65. What is the spinal cord?
    Central nervous system pathway responsible for transmitting sensory input from the body to the brain & for conducting motor impulses from the brain to the body muscles & organs.

    Acts as a reflex center
  66. What is the anterior medial fissure?
    Deep crease along the ventral surface of the spinal cord that divides the cord into right & left halves
  67. What is Posterior Medial Sulcus?
    Shallow longitudinal groove along the dorsal surface of the spinal cord
  68. What is Gray Matter of the spinal cord?
    Areas in the CNS dominated by nerve cell bodies; the central portion of the spinal cord
  69. What is the white matter of the spinal cord?
    Material that surrounds gray matter in the spinal cord

    Made up largely of axons
  70. What are Ascending Tracts?
    Bundles of axons along the spinal cord that transmit signals from the body to the brain
  71. What are the '3' Ascending Tracts?
    • Fasciculus Gracilis
    • Fasciculus Cutaneous
    • Spinothalamic Tracts
  72. What are the Fasciculus Gracilis & Fasciculus Cutaneous responsible for?
    • * Carry sensory impulses of light touch
    • * Vibration
    • * Positional sense from the skin, muscles, tendons & joints

    **Injury results in deficits on same side of body
  73. What is the Spinothalamic Tracts responsible for?
    • * Conducts pain & temperature (anterior)
    • * Conducts touch & pressure (lateral)

    ** Injury results in opposite side deficits
  74. What are Descending Tracts?
    Bundles of axons along the spinal cord that transmit signals from the brain to the body
  75. What are the '3' Descending Tracts?
    • Corticospinal Tract
    • Reticulospinal Tract
    • Rubrospinal Tract
  76. What is the Corticospinal Tract?
    Responsible for voluntary & fine muscle movement
  77. What is the Reticulospinal Tract responsible for?
    Consists of '3' subtracts: one lateral, one medial, one anterior

    Responsible for: sweating & muscular activity associated w/ posturing
  78. What are the rubrospinal tracts responsible for?
    Control the fine motor functions of the hands & feet
  79. What are Spinal Nerves?
    • Peripheral nerve roots that branch in pairs from the spinal cord
    • Have both sensory & motor components
    • Provide largest part of innervation to skin, muscles & internal organs
    • There are '31' pairs of spinal nerve roots
  80. What is a dermatome?
    Topographical region of the body surface innervated by one nerve root
  81. What are some of the 'key' locations to recognize for assessment for dermatomes?
    • C3: collar region
    • C7: little finger
    • T4: nipple line
    • T10: umbilicus
    • S1: small toe
  82. What is a myotome?
    muscle & tissue of the body innervate by a spinal nerve root
  83. What are some of the 'key' locations to recognize for assessment for myotomes?
    • C5: arm extension
    • C7: elbow extension
    • T1: knee extension
    • S1: ankle flexion
  84. What are the 12 pairs of spinal nerve roots?
    • C1-C8: Cervical
    • T1-T12: Thoracic
    • L1-L5: Lumbar
    • S1-S5: Sacral
    • Co: Coccygeal
  85. Each pair has '2' dorsal & '2' ventral roots. What do each of these do?
    • Ventral Roots: carry motor impulses from the cord to the body
    • Dorsal Roots: carry sensory impulses from the body to the cord
  86. What is a Plexus?
    Nerve roots converging in a cluster of nerves to form as a group
  87. What are reflexes?
    • Those primary processing functions that the spinal cord performs
    • Maintaining balance & muscle tone
  88. What are interneurons?
    Special neurons in the cord that intercept sensory signals from our 'reflex response'
  89. Definition of cranial nerves?
    12 pairs of nerves that originate in the brain & supply nervous control to the head, neck & certain thoracic & abdominal organs
  90. What are the 12 cranial nerves?
    • I: Olfactory nerve - smell
    • II: Optic nerve - vision
    • III: Oculomotor nerve - eye movement, pupil constriction
    • IV: Trochlear nerve: ocular movement
    • V: Trigeminal nerve: sensitivity of face
    • VI: Abducens nerve: Ocular movement
    • VII: Facial nerve: facial expression
    • VIII: Acoustic nerve: hearing
    • IX: Glossopharyngeal nerve: viseral sensibility
    • X: Vagus nerve: involuntary muscle control
    • XI: Spinal accessory muscle: speech
    • XII: Hypoglossal nerve: movement of tongue
Card Set
Chap 3 - Nervous System.txt
Nervous System