development

Question 1

how do somatic + ANS nerves travel

Answer 1

somatic and sympathetic ANS nerves travel together

Question 2

2 types of sympathetic ganglia

Answer 2

paravertebral = sympathetic chain T1 - L2 and prevertebral splanchnic nerve T5 to L2

Question 3

3 ganglia in prevertebral splanchnic nerve? what spinal levels

Answer 3

T5 to L2. celiac, superior and inferior mesenteric ganglion

Question 4

paravertebral preganglionic cell bodies: neurons at which levels? post ganglionics?

Answer 4

T1 to L2. but post ganglionic neurons project to entire body

Question 5

white or grey ramus communicasns?

Answer 5

white = myelinated, preganglionic sympathetic. grey ramus = unmyelinated post synpatic

Question 6

sympathetic NS: regardless of target, all begin?

Answer 6

the same: preganglionic short myelinated axons exit SC through ventral root and enter spinal nerve. exit spinal nerve via white ramus communicantes. enter sympathetic trunk/chain where post ganglionic neurons reside

Question 7

3 options for sympathetic NS

Answer 7

synapse in sympathetic chain ganglion then return to spinal nerve. ascend/descend within chain then synapse within the chain and return to spinal nerve at that level. enter sympathetic chain, pass through w/o synapsing and form splanchnic nerve towards abdominal organs, synapse in prevertebral ganglion

Question 8

sympathetic splanchnic: what levels

Answer 8

T5 to L2

Question 9

parasympathetic: innervation

Answer 9

cranial nerves 3, 7, 9, 10 (vagus) for visceral organs of thorax + abdomen. sacral parasympathetics S2 - 4

Question 10

5 steps for development of ANS

Answer 10

neuroblast formation. neuronal migration. differentiation. axon guidance. synpatogenesis.

Question 11

CNS and PNS come from?

Answer 11

neurulation - neural tube = CNS = cranial nerves and preganglionic cell bodies. neural crest = PNS = post ganglionics

Question 12

neurulation: steps involved and what 3 choices

Answer 12

notochord sends signals. neural plate then neural tube = CNS. some signal = neural crest = PNS. no signal = epidermis

Question 13

somites

Answer 13

become other parts of body, but will give signals to migrating neural crest cells to turn into ANS, melanocytes, sensory neurons, etc.

Question 14

what makes CNS + PNS (general)

Answer 14

tube = CNS. crest = PNS

Question 15

what is derived from neural tube? what isn’t?

Answer 15

CNS and all preganglionic ANS neurons from neural tube. PNS and post ganglionic ANS neurons are from neural crest

Question 16

preganglionic sympathetic and sacral parasympathetic derived from

Answer 16

cells in the intermediate grey matter of the spinal cord = neural tube

Question 17

pre and post ganglionic sympathetic neurons: what lvels

Answer 17

pre = T1 - L2. post = C1 to Cx1

Question 18

cranial sympathetic nerve levels

Answer 18

T1 - T5

Question 19

post ganglionic parasympathetic development

Answer 19

from neural crest. migrate short distances