19.6 NS: Development of the NS Flashcards
What are diseases of failure of the neural fold closure?
Anecephaly, spina bidfida
What is the gradient (direction) in the formation of the nervous system?
Rostral to caudal
How thick is the neural tub initially? How many vesicles does it form?
One cell thick
Forms three distinct vesicles (forebrain, midbrain and hindbrain)
What splits into the telencephalon and diencephalon?
The prosencephalon
What do the telencephalon and diencephalon become?
Tele: cortex, basal ganglia, hippocampus
Dien: thalamus, hypothalamus
What are some derivatives of the neural crest?
PNS, melanocytes, muscle cartilage/skull bone/jaws/face, dentine
What does the neuroepithelium do? Where is it derived from?
Adds layers to generate the cortex. Derived from neural tube
Where are all new neurons born?
At the ventricular surface
What can Reelin or DCXZ mutations result in?
Mental retardation
What is the most common cause of male autism? What mutation is it due to?
Fragile X syndrome
FMR1 gene
What do somites, notochord and neural tube develop into?
Somites: developing muscle and bone
Notochord: centre of vertebral body
Neural tube: spinal cord
What are motor neurons in the ventral horn driven by?
Interneurons
What does the topographic organisation of the spinal cord mean?
Neurons controlling distal muscle are lateral
What is the role of the floor plate?
It induces ventral horn motor neurons (signalling gradient)
Are axons present when a neuron first forms?
What are axon tracts laid down by?
Nope
Pioneer axons
