Neuro Exam 1.5 Part 1

Card Set Information

Neuro Exam 1.5 Part 1
2013-01-30 18:54:19
neurology neuroscience anatomy

review of lecture 5 for neuro exam 1
Show Answers:

  1. Is the spinal cord part of the CNS or PNS?
  2. What embryologically forms the spinal cord?
    neural tube
  3. The lateral walls of the neural tube thicken to form:
    small lumen (central canal)
  4. How long is the central canal?
    runs length of spinal cord
  5. What does the central canal become?
    ventricular system of the brain
  6. What is the ventricular system of the brain filled with?
  7. The central canal and ventricular system are continuous at what level?
    level of magnum foramen (at 4th ventricle)
  8. What is the sulcus limitans?
    indentation of central canal
  9. What is the purpose of the central canal?
    divide spinal cord (neural tube) into dorsal and ventral halves
  10. What is the alar plate?
    lateral walls of the dorsal half of the spinal cord
  11. What does the alar plate develop into?
    sensory structure/function (dorsal horn)
  12. What is the basal plate?
    lateral wall of ventral half of the spinal cord
  13. What does the basal plate develop into?
    motor structure/function (ventral horn)
  14. What are the 3 embryonic layers of the CNS?
    • ventricular zone
    • marginal zone
    • mantle zone
  15. What is another name for the ventricular zone?
    ependymal layer
  16. What is the first layer of the CNS to form?
    ventricular zone
  17. What is the second layer of the CNS to form?
    marginal zone
  18. What is the third layer of the CNS to form?
    mantle zone
  19. What is the innermost embryonic layer of the CNS?
    ventricular zone
  20. What is the middle embryonic layer of the CNS?
    mantle zone
  21. What is the outermost embryonic layer of the CNS?
    marginal zone
  22. What does the ventricular zone surround?
    central canal
  23. What does the ventricular zone produce?
    • neurons (motor or sensory)
    • glial cells (astrocytes and oligodendrocytes)
  24. The marginal zone is formed as...
    the outer layer of ventricular zone differentiates and the neuron is displaced laterally
  25. What does the marginal zone become?
    white matter
  26. Are cellular processes in the marginal zone myelinated?
  27. Is the marginal zone cellular or acellular?
    acellular, contains axons and dendrites of cell w/in ventricular layer (does not contain neurons)
  28. The mantle zone is the product of what?
    neuroblasts (immature neurons) that develop in the ventricular layer then migrate laterally into the mantle layer
  29. What does the mantle zone produce?
    neurons of ventral and dorsal horn (motor, interneurons, projection neurons)
  30. What are the different spinal cord meninges?
    • dura mater
    • leptomeninges
  31. Where does dura mater come from?
    (pachymenix) from mesoderm
  32. Where is the dura mater on the spinal cord?
    outermost layer
  33. What are the leptomeninges a product of?
    neural crest/ectoderm
  34. What are the two types of leptomeninges?
    • arachnoid mater
    • pia mater
  35. What layer of the spinal cord is pia mater?
    innermost layer
  36. How are neurons myelinated in the embryo?
    insulates axons in concentric layers with phospoholipids
  37. When does myelination in the embryo begin?
    4.5 months in gestation through 1st post natal year (SC)
  38. At birth, where does brain myelination occur?
    it is limited to only a few areas of the brain
  39. When does the brain complete myelination?
    25 years of age
  40. Where does myelination in the embryo begin?
    • proceeds from back of cerebral cortex to ventral portion
    • Myelination starts posteriorly and moves anteriorly; also begins inferiorly and works up superiorly
  41. What explains teenagers not so well thought-out behavior?
    frontal lobe is not fully myelinated because it is the last to be myelinated
  42. Why is the brain myelinated in the order it is?
    • primitive life sustaining areas are myelinated first
    • Like the brain stem, it is important for life so it is good that it is myelinated first
  43. In general, aspects of CNS, fiber tracts (in brain or spinal cord) will become functional when...
    myelination is complete
  44. Rostral
    toward the front
  45. Does the rostral end of the neural tube grow rapidly or slowly?
  46. What occur at 28 days of embryonic development?
    • neural tube forms prosencephalon, mesencephalon, and rhombencephalon
    • neural tube bends ventrally to form transitions
  47. What does the prosencephalon become?
  48. What does the mesencephalon become?
  49. What does the rhombencephalon become?
  50. What three transitions are formed at 28 days of embryonic development?
    • midbrain flexure
    • pontine flexure
    • cervical flexure
  51. What is another name for the midbrain flexure?
    cephalic flexure
  52. Where is the midbrain flexure?
    between forebrain and midbrain
  53. Where is the pontine flexure?
    between pons and hindbrain (medulla)
  54. Where is the cervical flexure?
    the transition between hindbrain and spinal cord
  55. What occurs at 35 days of embryonic development?
    the brain forms 5 vesicles
  56. How many vesicles does the forebrain form at 35 days of embryonic development?
  57. How many vesicles does the midbrain form at 35 days of embryonic development?
  58. How many vesicles does the hindbrain form at 35 days of embryonic development?
  59. What forms the forebrain?
  60. What forms the midbrain?
  61. What forms the hindbrain?
  62. What are the vesicles of the prosencephalon/forebrain?
    • telencephalon
    • diencephalon
  63. What is another name for the telencephalon?
  64. What is another name for the diencephalon?
  65. What does the telencephalon form?
    cerebral hemisphere
  66. What does the diencephalon form?
    thalamus structures
  67. What are the vesicles of the rhombencephalon/hindbrain?
    • metencephalon
    • myelencephalon
  68. What does the metencephalon become?
    cerebellum and pons
  69. What does the myelencephalon become?
    medula oblongata
  70. What occurs at 5 weeks of embryonic development?
    • refinement and diversification of vesicles
    • central canal develops into ventricular system
    • telencephalon grows over diencephalon
  71. Embryonic origins of the PNS are made up of:
    • 12 crainal nn
    • 31 spinal nn
    • sympathetic an dparasympathetic nn
  72. The majority of PNS comes from what embryonic structure?
    • neural crest
    • Exceptions:
    • -lower motor neurons of PNS are in ventral horn of SC--from neural tube
  73. What does the neural crest form?
    • all sensory neurons of the PNS
    • schwann cells
    • autonomic NS ganglia
  74. Where are the spinal nn and automatic sensory neurons cell bodies of the PNS located?
    in the dorsal root ganglia
  75. Where are cranial nn cell bodies of the PNS located?
    • in ganglia in the head and neck
    • -cranial nn V, VII, VIII, IX, X associated w/ ganglia (sensory function)
  76. Which cranial nerves are outgrowths of the brain and not nerves?
    olfactory (I) and optic (II) therefore, they are products of the neural tube
  77. What do schwann cells do?
    myelinate neurons in peripheral nn (sensory and motor)
  78. Which pre and postganglionic neurons of the autonomic NS synapse?
    both sympathetic and parasympathetic of ANS
  79. Where do preganglionic neurons come from?
  80. Where do preganglionic neurons synapse?
    at a ganglia w/ post-ganglionic to go to a target structure
  81. What embryonic structure forms postganglionic fibers?
    neural crest (motor neurons, efferent in nature)
  82. What embryonic structure forms preganglionic fibers?
    mantle of neural tube
  83. All motor neurons of the PNS have their cell bodies located where?
    in the ventral horns of the spinal cord and are products of the neural tube