Cranial Cavity, Spinal Cord, & Cell Biology Flashcards
cranial cap
frontal, parietal, temporal, occipital
cranial walls
frontal, parietal, temporal, occipital, sphenoid
basicranium
frontal, ethmoid, sphenoid, temporal, occipital
can be divided into 3 cranial fossa
what divides the anterior and middle cranial fossa?
sphenoid crest
what divides the middle and posterior cranial fossa?
superior border of petrous part of temporal bone
foramina in anterior fossa
olfactory foramina, CN I
foramina in middle fossa
optic canal, superior orbital fissure, foramen rotundum, ovale, spinosum, carotid canal
CN II, III, IV, V, VI, middle meningeal, internal carotid
foramina in posterior fossa
internal acoustic meatus, jugular and hypoglossal foramen, foramen magnum
CN VII, VIII, IX, X, XI, XII, vertebral arteries, spinal cord
what are the meninges and spaces?
dura, arachnoid, and pia mater
epidural (adipose), subdural (potential), subarachnoid (CSF)
what two layers is the cranial dura mater made up of?
periosteal and meningeal layer
periosteal layer
adherent to the cranium, continuous with external periosteum of skull
meningeal layer
continuous into the vertebral layer
when is the meningeal layer not fused to the periosteal layer?
to form dural infoldings and dural venous sinuses
what is the spinal cord a continuation of?
the caudal medulla at the foramen magnum
where vertebral level does the spinal cord end at?
L1/L2
segmental medullary arteries
anastomose with spinal arteries, mainly at cervical and lumbar enlargements
radicular arteries
supply posterior and anterior nerve roots
where do cervical spinal nerves exit?
above the vertebrae of the same level
where do all other spinal nerves exit?
below vertebrae of the same level
what is gray matter?
unmyelinated cell bodies of lower motor neurons, interneurons, sensory projection neurons
what is white matter?
myelinated axons (ascending and descending tracts)
cervical spinal cord cross section characteristics
thickest white matter, large ventral horns, gracilis and cuneate fascicles
thoracic spinal cord cross section characteristics
little gray matter, contains lateral horn for IMLCC
what to know about reflexes??
unipolar neuron in humans
uncommon, exocrine gland secretion and smooth muscle contractions
many sensory neurons are
bipolar/pseudounipolar
most brain/spinal cord neurons and motor neurons are
multipolar
where are ependymal cells found?
line all ventricles of the brain and central canal of spinal cord
what do standard ependymal cells do?
help to circulate CSF through ventricular system, contain microvilli to assist
what do modified ependymal cells form?
the choroid plexus
what is the function of microglia?
phagocytotic scavenger cells, destroy invaders, remove debris, promote tissue repair
what is the function of astrocyte?
glia critical for neuronal nourishment and synapse development and function
regulate extracellular ion and neurotransmitter concentrations
oligodendrocytes
myelinating cell of CNS
Schwann cells
myelinating cell of the PNS
