Spinal Cord Flashcards
How is a bundle of neurones termed differently in the CNS vs PNS
Tract, nerve
How is a body of axons termed differently in CNS v PNS
Nucleus, Ganglion
A branch of an axon is a
collateral
Briefly outline neural tube formation
- Neural plate epithelium
- Epithelium is folded to form a groove
- Neural crest + Neural tube cells
What occurs when neural tube doesn’t close?
Anencephaly and spinal bifida
Which vitamin helps with neural tube formation?
Folic acid
What are the different meninges?
- Dura
- Arachnoid
- Pia
What does the subarachnoid space contain?
CSF - allows CNS to float
What connects pia and arachnoid layers?
Denticulate ligament
What are the segments of the spinal cord named after?
The spinal nerve to which they give rise
Name segments and lengths of spinal cord from top to bottom
- Cervical 1-8
- Thoracic 1-12
- Lumbar 1-5
- Sacral 1-6
- Coccygeal
At which segment and number does the spinal cord end and how does this differ from at birth
L1 and L3 at birth
Cervical enlargement extends from
C5 - T1
Cervical enlargement is due to
large nerves which supply upper limbs
Lumbar enlargement extends from
L1-S2
What extends beyond the end of the spinal cord?
Nerve roots
Tapered lower end of spinal cord
Conus medullaris
After the spinal cord tapers out, the spinal nerves branch out diagonally forming the
Cauda equina
Cauda equina consists of
L2-L5 nerve pairs
The rostral end of the neural tube expands to form
the brain
2 outgrowths of of forebrain vesicles
- Telencephalon
2. Diencephalon
Choroid plexus
Plexus of cells that produce CSF - largely in lateral ventricles
Brainstem function
Midbrain: vision, brain, hearing, eye + body movement
Medulla: passive body needs
Pons: motor control + sensory analysis
Diencephalon includes
Hypothalamus + thalamus
Cerebral aqueduct connect
3rd + 4th ventricle
