L2

Question 1

Early neuralation

Answer 1

Neural plate- neural induction leads to generation of the neural plate on the dorsal side of the vertebrate embryo (neural place consists of NSCs (neuroepithlial cells) that generate NS

Question 2

Late neuralation:

Answer 2

Neural tube- lateral edges of neural plate fold up and over to become dorsal side of neural tube (roof plate); midline doesn’t move (floor plate); this occurs at different times along r-c axis (plate zips together to form tube; rostral failure-> anencephaly, caudal failure-> spina bifida; anterior neural tube also causes formation of pan placodal ectoderm -> generates specialised structures in head region

Question 3

Hindbrain

Answer 3

Mesencephalon- pretectum(d), tectum(d), tegmentum(v); Metencephalon- cerebellum(d), pons(v); Myelencephalon- medulla oblongata; +SC

Question 4

What features are cranial and trunk neural crest responsible for in the peripheral nervous system?

Answer 4

Cranial- SS neurons, trigeminal ganglia and facial bones

Trunk- SS neurons and VS neurons (DRG)

Question 5

What features are cranial and trunk neural crest responsible for in the autonomic nervous system?

Answer 5

Cranial- ganglionic neurons of the parasympathetic

Trunk- ganglionic neurons of the sympathetic

Question 6

What does the preganglionic ANS consist of?

Answer 6

VMNs from neural tube region Vp3

Question 7

Where do AChergic MNs come from?

CNS

Answer 7

SMNs from pMN region of neural tube; BMNs from Vp3

Question 8

Which regions do INs come from?

Answer 8

Dp1-6, Vp0-2

Question 9

Mature SC

Answer 9

Ascending- dorsal column (tactile, first order Ns; spinothalamic tracts; spinoreticular tracts (fast pain, second order Ns)
Descending- lateral (corticospinal (rubrospinal)) pathway; ventromedial pathway
Everything but pain: DRG (1)-> medulla (2) -> descussate to thalmus -> (3) to sensory cortex
Pain- spinothalamic tract via fast Aδ fibres