Human CNS Development Flashcards
What are the primary brain vesicles
prosencephalon, mesencephalon and rhombencephalon
What are the secondary brain vesicles
diencephalon, metencephalon, telencephalon and myelencephalon
Describe the secondary brain vesicles
flexions and out pocketings
Where is white matter located in the spinal cord
outside
What is the white matter in the spinal cord
myelinated axons
Where is grey matter located in the spinal cord
inside
What is the grey matter in the spinal cord
soma of neurones
How is matter arranged in the spinal cord
opposite to the brain
Where are the cell bodies of afferent fibres located in the spinal cord
dorsal root ganglion
What do dorsal roots carry IN to the spinal cord
sensory input
What do ventral roots carry OUT of the spinal cord
motor commands
What do interneurons connect
sensory and motor neurons
What are interneurons important for?
stretch reflexes
What reflex doesn’t use interneurons
Tendon jerk reflex
Why doesn’t the tendon jerk reflex use interneurons
monosynaptic
What are the meninges of the spinal cord
pia, arachnoid, and dura
Describe the pia mater
thin, soft, innermost
Describe the arachnoid mater
middle, with blood vessels, cobweb look
Describe the dura mater
tough, double layer
What are the two layers of the dura
endosteal and meningeal
Which layer of the dura is true dura mater and deepest
meningeal
Where does the CFS flow?
central canal, brain ventricles, subarachnoid space
What is the function of the CFS
float and cushions the CNS
What forms the cerebrospinal fluid
choroid plexus
What absorbs the CFS
arachnoid granulations
How is the CSF sampled?
lumbar puncture between L3 and L4
What does CSF composition give information about?
state of the CNS
Name two disorders of CSF flow
hydrocephalus and coning
What are the symptoms of hydrocephalus
disturbances in fluid, increased intracranial pressure, cell death
What are the symptoms of coning?
high BP, low HR, loss of brainstem reflexes
Describe the BBB
semi permeable membrane
What does the BBB separate
blood from CSF
What can pass through the BBB
small molecules, fat soluble molecules, some gases
What CANNOT pass through the BBB
cells, particles, large molecules
