nervous system structure through development

Question 1

whats The Neural Plate ~ 17 days old

Answer 1

-endoderm (all internal organs) : Lining of viscera
-mesoderm: bones and muscles
-ectoderm: Skin and nervous system

Question 2

what happens with Neurulation ~ 22 days old

Answer 2

-neural plate -> neural groove and folds-> neural tube (CNS) +ventricular system OR neural crest (PNS)
-every single neurone derives from the neural tube
-somites become muscle in adults -> somatic NS innovates somites (comes from)

Question 3

What neurons could form from the neural crest

Answer 3

-sensory neurones
-dorsal root ganglion neurone
-parasympathetic neurones

Question 4

Why are women advised to take Folic Acid when trying to conceive and during pregnancy

Answer 4

-Failure to appropriately close the neural tube
-Specific sequences of gene expression – influenced by environment
-Folic acid = 90% reduction = influences DNA synthesis
-take folic acid so neural tube forms properly
-folic acid is a coenzyme- production of thymine, less thymine means less DNA synthesis therefore leads to issues such as anecephaly (forebrain doesnt develop- fatal) or spina bifida (corral part of spinal tube doesnt shut properly, not fatal)

Question 5

what are the 3 primary brain vesicles

Answer 5

1) prosencephalon or forebrain
2) mesencephalon or midbrain
3) rhombencephalon or hindbrain

Question 6

what are the Secondary brain vesicles of the forebrain

Answer 6

-forebrain contains:
=telencephalic vesicles
=diencephalon (centre)
=optic vesicles -> Optic stalk and optic cup

Question 7

What do the optic stalk and optic cup develop into

Answer 7

-optic nerve: stalk
-cup: retina
-optic nerve and retina are composed of axons and retinal ganglion neurones

Question 8

Forebrain differentiation

Answer 8

-main divisions:
=diencephalon
=telencephalon
-ventricles:
=third ventricle
=lateral ventricles
-grey matter:
=cerebral cortex
=thalamus- relay centre that comes from lower down in the brain in the cortex
=hypothalamus
=basal telencephalon
-white matter:
=corpus callous- connect sone cerebral hemisphere to another
=cortical wite matter
=internal capsule

Question 9

midbrain differentiation

Answer 9

-evolutionary
- cerebral aqueduct- easily blocked
-tectum- dorsal
-tegmentum- ventral, 2 functionally distinct areas

Question 10

the midbrain functions

Answer 10

-pain (control of)
-processing of vision
-motor functions
-auditory functions

Question 11

Hindbrain Differentiation

Answer 11

-rhombic lips develops into cerebellum
-medulla doesnt expand much

Question 12

what does the cerebellum do

Answer 12

-Co-ordination of movement, balance, posture
-10% CNS volume: 50% CNS neurons
-1:40 neuronal outputs to inputs
-Vestibulocerebellum - oldest - balance
-Spinocerebellum - muscle stretch receptors
-Cerebrocerebellum - projections from sensorimotor cortex - motor coordination