Development of the CNS Flashcards
What are the precursors to the CNS and PNS
wall of neural tube (neuroepithelium) -> CNS
Neural crest -> PNS
What are the cell types that differentiate from neuroepithelium
Neuroblasts
Glioblasts
Ependymal cells
What are neuroblasts
All neurone with cell bodies (CNS)
What are glioblasts
supportive cells of the CNS, and include astrocytes +
oligodendrocytes (myelin forming cells)
What are ependymal cells
Lining ventricles and central canal
What are the layers of the neuroepithelium from inside to outside
Ependymal (developmental cells) Grey matter (migrated cells from ependymal) White matter (axons and processes of the neurons)
What are the layers of the neural tube from inside to the outside + draw
Ependymal (germinal) Floor plate Grey matter (mantle) Roof plate White matter (marginal) Neural crest (dorsal)
What controls differentiation of the neural tube cells
Signalling molecules (secreted by surrounding tissues) interact with neuroblast receptors Controls migration and axonal growth by attraction and repulsion
What does differentiation of the neural tube cells depend on
Concentration gradient and timing
Draw and label a developing spinal cord
Neurons are innermost, made up of interneurons above and motorneurons interneurons below
Neural crest cells form sensory neurons in dorsal root ganglion
Label a mature spinal cord
Central canal surrounded by the ventral and dorsal horns.
Surrounded by white matter which extends into the ventral and dorsal roots (+ dorsal ganglion)
Draw and label the developing brainstem
Fourth ventricle surrounded by the roof plate above and the sulcus limitans below. Below this lies the basal plate innermost and the alar plate
Draw and label the developing brain at 5 weeks
Telencephalon (fore) Diencephalon (fore) (mid) Pons (hind) Medulla (hind)
Draw and label the developing brain at 8 weeks
Developing hemisphere (fore) aqueduct (mid) Developing cerebellum (hind)
What are some processes involved in development
Proliferation Differentiation Migration Axon growth Synapse formation