Central Nervous System Flashcards
where do the brain and spinal cord lie?
within the skull and vertebral canal
what protects the brain and spinal cord?
it is covered by meninges
- dura mater- outer
- arachnoid membrane
- pia mater- inner
what are the segments of the spinal cord?
- cervical
- thoracic
- lumbar
- sacral
- coccygeal
(top to bottom)
what part of neurons make up grey matter?
neuron cell bodies and some axons
what part of neurons makes up white matter?
axons (myelination has high fat content)
what does the dorsal (posterior) part of the spine contain?
cell bodies of second- order sensory neurons
what does the ventral (anterior) part of the spine contain?
cell bodies of motor neurons
what does the ventral (anterior) part of the spine contain?
cell bodies of motor neurons
how does matter stain appear when STAINED FOR MYELIN?
white matter appears dark, grey matter appears pale
why is there more white matter in cervical and thoratic regions than lumbar and sacral?
caused by the many axons going up to the brain from all levels of the spinal cord AND there are many axons traveling from the brain down to different segments of the spinal cord
which axons enter the spinal cord?
sensory axons
which axons leave the spinal cord?
motor axons
describe the reflex pathway
stimulus
sensory neuron in
interneuron in the spine
motor neuron out
response
what is the set up of matter in the spinal cord?
white matter surrounds grey matter
what is the set up of matter in the brain?
grey matter is on the outside- cerebral cortex
