Neuroembryology S2M1

  1. When does neurulation begins
    22 days after conception
  2. The cranial end of the neural tube closes when
    Day 25
  3. The caudal end of the neural tube closes when
    Day 27-28
  4. Sonic hedge hog genes control what development
    The basal/ventral end of neurulation
  5. BMP and PAX are genes that control what
    Dorsal/Alar neurulation
  6. The Alar end of the neural tube develops into what type of nerves
  7. The Basal end of the neural tube develops into what type of nerves
  8. The neural tube is composed of what type of cells
    Pseudo stratified epithelium
  9. All cell divisions in the spinal cord happen where
    The luminal surface (inside of tube)
  10. Grey matter is made up of what cells
    • Interneurons
    • Motorneurons
    • Blood vessels
    • Glial cells (supporting cells)
  11. What type of neuron connections allow for more control of function
    Polysynaptic, the motor interneurons between incoming sensory and outgoing motor, the more control one has on their actions
  12. What is the difference in the growth of neurons attaching to the Basal and Alar plates
    • Motor neurons are an outgrowth from the Basal plate
    • Sensory nerves form an ingrowth to the Alar plate from the dorsal root ganglion
  13. What is the difference in the myelin sheath in the PNS and CNS
    • In the PNS they are formed by Schwann cells only
    • In the CNS they are formed by Oligodendroglia only
  14. Alar plate forms sensory interneurons when triggered by
    TGFb family of growth factors
  15. Monosynaptic reflexes
    • No interneurons, single chemical synapse
    • A reflex arc consisting of only two neurons, one sensory neuron, and one motor neuron
    • Has a short duration
  16. Polysynaptic reflex
    One or more interneurons connect afferent (sensory) and efferent (motor) signals. All but the most simple reflexes are polysynaptic, allowing processing or inhibition of polysynaptic reflexes within the spinal cord
  17. All of the tendon reflexes are polysynaptic accept which
    • Knee
    • Achilles
    • Bicipital
  18. Meninges arise from what embryonic origin
    Mesoderm surrounding neural tube
  19. An epidural hematoma is most often caused by a tear of
    Middle meningeal artery
  20. The dura and arachnoid have close relationship that can be altered how
    Ruptured blood vessel between them causing a subdural hematoma (slow bleed)
  21. What is the difference between a meningocele and a meningomyelocele
    • Meningocele is when the cyst on the exterior is simply filled with spinal fluid.
    • Meningomyelocele is when the spinal cord accompanies the CSF in the cyst
  22. Rachischisis
    The most severe form of spina bifida where the neural tube fails fold and close remaining open to the external environment
  23. Procephalon/Forebrain are primary vesicles that make up what secondary vesicles
    • Telencephalon
    • Diencephalon
  24. Midbrain is a primary vesicle that makes up what secondary vesicles
  25. Rhombencephalon/Hindbrain are primary vesicles that make up what secondary vesicles
    • Metencephalon
    • Myelencephalon
  26. The olfactory bulbs come from what vesicle
  27. The Optic cups come from what vesicle
  28. What do all of the sensory nerves have to pass through before reaching the cerebral cortex
  29. What is the role of the hypothalamus
    It performs the primitive functions such as, Visceral (autonomic) nervous system, heart rate, increased blood flow, standing hair on end, peristalsis, motivation for food, drink, and sex.
  30. Basal ganglia is found where with what function
    Basal telencephalon and is involved in initiating voluntary movement involved in fear and emotion
  31. When does the development of the visual system begin
    Day 22 with the formation of the optic sulcus
  32. The optic vesicle consists of what tissue
  33. Optic vesicles arise from what
    It grows out of the Diencephalon (evagination)
  34. The optic cup and optic stalk arise from what
    Optic vesicle invaginating to forming a double layered optic cup and optic stalk
  35. What does the optic stalk eventually differentiate into by the ingrowth of axons from the ganglion layer
    • Optic Nerve
    • Optic Chiasm
    • Optic Tract
  36. What are the derivatives of the optic cup (neuroectoderm)
    • Retina
    • Iris
    • Ciliary body
  37. What separates the inner layer of the optic cup from the outer layer
    Intraretinal space
  38. What does the inner layer of the optic cup give rise to
    Neural retina containing rods, cones, bipolar and ganglion cells
  39. What does the intraretinal space make adults
    It is obliterated in adults but remains a weakened area prone to retinal detachment
  40. The epithelium of the iris develops from what
    Both layers of the optic cup
  41. What is the stroma of the eye and what does it develop from
    It is the framework of the eye and develops from mesoderm continuous with the choroid
  42. The epithelium of the ciliary body of the eye develops from
    Both layers of the optic cup
  43. What does the suspensory fibers of the lens develop from
    Ciliary muscle and ciliary processes
  44. Ciliary processes produce what found in the chamber of the eye
    Aqueous humor found between the lens and the cornea
  45. What does the hyaloid artery of the eye eventually form
    The central artery and vein of the retina
  46. The choroid fissure closes when
    Week 7
  47. The optic nerve, a tract of the diencephalon, has what interesting characteristics
    • Not completely myelinated until 3 months following birth
    • Not capable of regeneration
    • Surrounded by subarachnoid space
  48. How can an increase in the amount of CSF affect vision
    It puts pressure on the optic nerve causing edema of the optic disk (papilledema)
  49. What portion of the eye is derived from ectoderm
    Cornea, lens, retina, the rest from mesoderm
  50. What is the substance found between the retina and lens
    Vitreous body (gelatinous substance)
  51. Coloboma is when
    There is a failure of the choroid fissure to close in the eye producing a dark notch within the iris (droplet looking eye)
  52. Catarects is when
    The lens is opaque, this can be inherited or caused by maternal rubella or exposure to radiation during pregnancy
  53. Congenital Glaucoma
    Abnormal development of the drainage of aqueous humor, may be caused by rubella or inherited recessive gene
  54. Microphthalmos
    • Underdeveloped eye usually accompanies other craniofacial abnormalitites.
    • Can be caused by Cytomegalvirus or Toxoplasmosis
  55. Cryptophthalmos
    Absence of eyelid
  56. Anophthalmos
    Absence of entire eye, rare
  57. What are the adult derivatives of the optic vesicle, a secondary vesicle of the forebrain
    • Retina
    • Optic nerve
  58. What is the adult derivative of the thalamus (diencephalon)
    • Dorsal thalamus
    • Hypothalamus
    • Third ventricle
  59. What are the derivatives of the Telencephalon
    • Olfactory bulb
    • Cerebral cortex
    • Basal Telencephalon
    • Corpus callosum
    • Cortical white matter
    • Internal capsule
  60. The Tectum is found where and differentiates into what structures
    Midbrain, and develops into the superior and inferior Colliculus
  61. Tagentum is found where and contains what
    Midbrain, it is the most colorful area of the brain and contains the substantia nigra and the red nucleus (both are involved in voluntary movement)
  62. A malformation of the substantia nigra can result in what
    Parkinsons disease
  63. Damage to the cochlear nuclei will result in
  64. What are the adult derivatives of the midbrain
    • Tectum
    • Tegmentum
    • Cerebral aquaduct
  65. What are the adult derivatives of the Hindbrain
    • Cerebellum
    • Pons
    • Fourth ventricle
    • Medulla
  66. The external ear is derived from what
    1st pharyngeal groove
  67. The auricle (ear lobe) develops from six mesenchymal projections composed primarily of what cells
    Neural crest cells called auricular hillocks
  68. The tympanic cavity (middle ear) is derived from
    1st pharyngeal pouch
  69. The malleus, incus, and stapes are derived from what
    • Malleus and incus 1st pharyngeal arch
    • Stapes 2nd
  70. The tensor tympani, the muscle attached to the malleus arises from, and is innervated by what
    First pharyngeal arch, innervated by cranial nerve V1
  71. The stapes is controlled by what muscle and innervation
    Stapedius muscle arising from the 2nd arch, innervated by the 7th cranial nerve
  72. The tympanic plexus in the ear is formed by what nerve
    9th cranial nerve (Glossopharyngeal)
  73. The membranous labyrinth contains
    All the structures derived from the Otic vesicle
  74. The inner ear develops from what
    Ectodermal depressions on the lateral surface of the Rhombencephalon/Hindbrain called optic placodes at day 22
  75. What is the difference between communicating and non communicating hydrocephalus
    • Communicating is when the arachnoid granulations aren't functioning properly and therefore CSF isn't leaving through the venous sinuses
    • Non communicating is an obstruction between ventricles
  76. When do the posterior and anterior fontanelles on a baby close
    • Posterior 3-6 months
    • Anterior 18 months
  77. The choroid fissure closes, optic nerve, and inner ear are all formed at what week
  78. Myelination of the peripheral nerves begins at what week
    16 (4th month)
Card Set
Neuroembryology S2M1