LABORATORY Seven

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LABORATORY Seven

• The Central Nervous System
• (Brain Spinal Cord)

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Nervous Tissue

• Neurons functional cells that transport
  electrical impulses
• Neuroglia non-conductive cells
• Schwann cells

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Human Brain
Transverse fissure
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Human Brain Right Half
Septum pellucidum
Fornix
Choroid Plexus
Optic Chiasma
Corpora quadrigemina
Mammilary body
Cerebral aqueduct
Fourth ventricle
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Human Brain VentriclesVentricles are a complex
series of spaces within the hemispheres of brain
which produce and house CSF.
Site of massa intermedia
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Dura Mater in Cerebral Meninges

• Modified in two areas
• Falx cerebri penetrates longitudinal fissure
  between brain hemispheres
• Tentorium cerebelli penetrates transverse
  fissure that separates the cerebrum from the
  cerebellum

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Spinal Cord Meninges
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Cross-Section of Spinal Cord
Dorsal gray horn
White matter
Ventral gray horn
Central Canal
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Human Spinal Cord Model
Conus medullaris letter d Filum terminale
letter e Cauda equina around letter e
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Sheep Brain DissectionGoogle search under
image for Sheep brain dissection

• Each lab pair should obtain a sheep brain,
  dissection tools, and a tray
• Choose a sheep brain with intact pituitary gland
  if possible!
• Note the 1800 relationship between the cerebrum,
  cerebellum, and spinal cord
• Identify the superficial structures
• Identify the longitudinal fissure and transverse
  fissure, but the central and lateral fissures can
  not be identified on the sheep brain
• Grasp the sheep brain gently by the cerebral
  hemispheres and the cerebellum, and separate them
  at the transverse fissure to see the corpora
  quadrigemina (superior inferior colliculi)
  pineal body
• To prepare for pituitary gland removal, carefully
  cut Trigeminal cranial nerve V, 1cm above its
  attachment site to the brain
• When removing the pituitary gland, look
  underneath it to make sure no cranial nerve is
  attached
• If you see a string structure attached to the
  pituitary gland from one side and to the floor of
  the brain from another side, clip it with a pair
  of scissors closer to the pituitary gland
• Identify cranial nerves I, II, III, IV, V, VI and
  XI
• Section the sheep brain by placing it ventral
  side up.
• Make a long, smooth, midsagittal cut. Be sure to
  completely divide the brain in half
• Identify the assigned structures
• Observe the prepared coronal section of the sheep
  brain and identify the assigned structures
• Take half of the dissected brain home, and return
  them to the lab when done.