Basic Topography And Development Of The Nervous System Flashcards
What is grey matter composed of?
Predominantly cell bodies and dendrites (although does contain some axons)
Is the cauda equina part of the CNS or PNS?
Part of the PNS, despite being in the vertebral column.
Of the ventral and dorsal horns, which contains motor and which contains sensory?
Sensory neurones come into the dorsal horn.
Motor neurones go out of the ventral horn.
What are Rexed’s laminae?
Organised columns within the grey matter.
What is white matter composed of?
Predominantly of axons (has no cell bodies).
What 3 components is white matter organised into?
Funiculi, tracts and fasciculi.
What is a funiculus?
Segment of white matter containing multiple tracts that travel in multiple directions.
What is a tract?
White matter pathway connecting 2 distinct regions of grey matter, impulses only travel in 1 direction i.e. Ascending or descending.
What is a fasiculus?
Subdivision of a tract that supplies a distinct area of the body.
What are the 3 parts of the brainstem?
Midbrain, pons and medulla.
Is the cerebral cortex grey matter or white matter?
Grey matter.
What are association fibres?
Connect cortical fibres within the same hemisphere.
What are commissural fibres?
Connect L + R hemispheres, or cord halves.
What are projection fibres?
Connect cerebral hemispheres with the cord/brainstem and vice versa.
Where is the primary motor cortex situated?
The pre-central gyrus.
Where is the primary sensory cortex located?
The post-central gyrus.
What embryological layer is the CNS derived from?
Ectoderm.
CSF is produced by what cells?
Choroid plexus cells.
What is the name of the connection between 3rd and 4th ventricles?
Aqueduct.
Where does CSF drain into after it has passed through the ventricles?
Subarachnoid space.
What can a folate deficiency lead to?
Neural tube defects.
What might a raised maternal serum alpha-fetoprotein indicate?
May indicate a neural tube defect. This protein is normally retained inside the foetus, but can leak out due to a defect.
What is the highest level of nerve roots contained in the cauda equina?
L2.
