Development Of The Nervous System Flashcards
Neurogenesis (notochord to neural tube)
Notochord causes the ectoderm to become a neuroectoderm. The middle begins to fold forming the neural tube which when closes forms the roof plate .
Neurogenesis (neural tube to 5 vesicles)
The anterior end of the neural tube forms the brain and posterior end forms the spinal cord. Then the neural crest separates which leads to a high degree of patterning, leading to formation of 3 vesicles then 5.
Neural tube close to somites forms what?
Spinal cord
Lumen of the neural tube form ventricles for what?
Cerebrospinal fluid
What are morphogens?
Chemicals that cause morphogenesis
What is morphogenesis?
The repressing or activation of transcription factors determining the identity of a cell.
What are HOX genes?
Family of transcription factors that establish segmentation along anterior-posterior axis
What happens if you don’t have SHH (sonic hedge hog) morphogen?
Leads to a lack of ventral identity and lack of different cells. Can lead to synophalamia (Cyclopia) as optical nerves don’t seperate
How are neurones formed?
Neuroblasts migrate to the pial surface to form the marginal zone and then differentiate into neurones
How are neural cortices formed?
From inside out
How are glia formed?
Generated from glioblasts. Either remain attached to the lumen or move to the marginal layer
What happens to glioblasts attached to the lumen?
They form ependymal cells
What’s an ependymal cell?
Cell that produces CSF
What happens to astrocytes that move to the marginal layer?
They form astrocytes or oligodendrocytes
How do neurones find their way?
Uses cues/signal such as morphogens to move from stepping stone to stone. They can also move by fasciculation.
