L2.1: Development of the Nervous System Flashcards
Morphogenesis
Patterning of neural tube
Neurulation
Formation of a rudimentary nervous system: The folding process in vertebrate embryos which includes the transformation of the neural plate into the neural tube. The embryo at this stage is termed the neurula.
Neurogenesis:
Production of neurons and glia from precursor cells
True or false: Neural tissue is derived from the ectoderm, which is also the source of the epidermis.
True.
Epidermal fate is determined by
local bone morphogenetic protein (BMP) signalling
Neural fate, rather than epidermal, is determined by
Signals from “organiser” region (e.g. Ng-Noggin, Chd - Chordin) that block the BMP signal, thereby inducing neural fate
At the rostral end, the neural tube divides to form which three segments?
Prosencephalon (forebrain) Mesencephalon (midbrain) Rhombencephalon (hindbrain)
Prosencephalon splits into:
Telencephalon and Diencephalon
Rhombencephalon splits into:
Metencephalon Myelencephalon
What induces the the patterning centre of the roof plate
the overlying ectoderm
Roof plate secretes which dorsalising morphogens
BMP, FGF, Wnts
What induces the floor plate
The underlying notocord
The floor plate secretes which ventralising morphogens
sonic hedgehog (legit)
Neuroepithelium
Primary germinal zone lining the ventricular system of the developing CNS
Symmetric divisions:
Self-renewal of progenitor cells Expand neuroepithelium progenitor pool (early) or give rise to two neurons (late) Produce two identical daughter cells
Asymmetric divisions:
Radial glia (RG) divide and produce: Another RG (self-renewal) and A differentiated neuron that cannot produce more neurons; produce two different daughter cells
True or false: The deepest layers of the cortical plate are produced last.
False, the deepest layers of the cortical plate are produced last.
Cortical inhibitory interneurons are produced in the
basal forebrain (MGE – medial ganglionic eminence) and migrate and then integrate into the developing cortical layers
Olfactory bulb neuroblasts migrate along the
rostral migratory stream (red arrow)
Cerebellar granule cell precursors migrate from the
rhombic lip
True or false: Neurogenesis precedes gliogenesis
True
The tip of a growing axon is called the
growth cone
True or false:
Synapse formation and myelination occur post-natally
True
True or false:
Neuronal migration and proliferation can occur after birth
False
