Development of the Peripheral Nervous System Flashcards
Where are the ganglia in the parasympathetic nervous system?
usually in wall of viscera
four cranial ganglia
When do PNS schwann cells myelinate nerves?
motor roots myelinated before sensory
fourth month
What is the sympathetic nervous system?
fight or flight
in thoraco-lumbar region
What does the neural tube below the 4th somite turn into?
spinal cord
what is the sulcus limitans?
line that divides neural tube into alar and basal plate
What does smooth and cardiac muscle form from?
splanchnic mesoderm
Where is a newborn’s spinal cord ending?
L2 or L3 (lower than an adult, if you were to do a lumbar puncture, have to go at L4/L5)
What does the 4th somite and above neural tube turn into?
brain
Where does the dorsal ramus go?
both motor and sensory neurons
motor –> dorsal muscles
sensory –> dorsal integument
What are SVE neurons?
Special/branchial visceral efferent
motor to muscles derived from pharyngeal arches = face and neck muscles
What are GVA neurons?
general visceral afferent = from NC
sensory of visceral structures (organs from endoderm or mesoderm adjacent to endoderm)
What is the parasympathetic nervous system?
rest and digest
cranial nerves
2nd to 4th sacral spinal nerves
In the ANS, where are post-ganglion cells? What are they derived from?
from ganglion to body part
derived from neural crest cells
What are SVA neurons?
special visceral afferent = from NC
chemical senses = taste and smell
What PNS cells develop from neural tube?
motor neurons
pre-ganglionic autonomic neurons
What things come from the ventricular zone?
ventrical cells and CSF
What are postganglionic neurons like in the sympathetic nervous system?
long
UNmyelinated
what is the basal plate?
anterior part of neural tube = motor
What types of PNS neurons come from neural crest?
Afferent = GSA, GVA, SSA, SVA
What type of tissue comes from the marginal zone?
myelinated neurons (white matter); oligodendrocytes are found here
In the ANS, where are pre-ganglion cells? What are they derived from?
extend from spinal cord to ganglia
made from neuroectoderm/neural tube
Where does the ventral ramus go?
both motor and sensory
motor –> limbs, lateral and ventral body wall
sensory –> integument of same regions
What are the neurons like in the parasympathetic nervous system?
prenganglionic = long and myelinated postganglionic = short and UNmyelinated
What PNS cells develop from neural crest?
neurons of dorsal root ganglia sensory ganglia of cranial nerves schwann cells sympathetic ganglia parasympathetic ganglia
