Cranial nerve overveiw Flashcards
How many pairs of CN? numbered in what order?
12 pairs
rostral to caudal (frontal lobe to medulla)
ALL cranial nerve except _____ are part of PNS?
1 and 2
CN 1 and 2 are part of ?
CNS, because they are extensions of the forbrain
all the cranial nerves are covered by? and all 3 layers of?
meninges and all layers of dura extend over the CN
Why is CN 3-12 part of PNS?
because the nerves extend outside of the brain and spinal cord (whereas 1 and 2 are extentions of forebrain)
all neural development is caused by?
external signalling
Shh in notochord signals development of?
other cells and dissentigrates to become part of vertebral column
What forms alar plate?
roof plate
What form basal plate?
floor plate
alar plate becomes?
posterior horn (sensory)
basal plate becomes?
anterior horn (motor)
Zone of autonomic neurons is located where and becomes?
located between alar and basal plate
becomes lateral horn (T1-L2)
Ectoderm - _____ plate -_____ plate - ______ horn-____ matter= sensory or motor
ectoderm- roof plate- alar plate-posterior horn- gray matter- SENSORY
Notochord - _____ plate -_____ plate - ______ horn-____ matter= sensory or motor
Notochord - floor plate -basal plate -anterior horn- gray matter= MOTOR
anterior or posterior horn sensory or motor
anterior= motor posterior= sensory
sensory nuclei are located more medial or lateral?
sensory= lateral motor= medial
development of what pushes the roof plate laterally (dorsal) to the side?
4th ventricle
*ventricles make cerebral fluid
motor or sensory = efferent or afferent
motor= efferent sensory= afferent
functional components of cranial nerves are defined and categorized by what 3 things?
1) efferent (motor) and afferent (sensory)
2) somatic or visceral
3) general or special
