Question

The following 5 stages are associated with early neural development: Neuron death, Process Growth and Synapse Formation, Aggregation, Proliferation, Migration. List these stages in the correct temporal order in which they occur, starting with the earliest, and describe in detail what happens in each stage

Answer 1

Neural development is the process of the development of the nervous system. It begins with the neural plate formation. The ectoderm overlying the plate signals the neural precursor cells to undergo rapid proliferation. The rapidly proliferating cells include neurons and glia. The neurons then use glial cells as tracts to migrate to their target location. Here, they begin aggregating and form networks with weak connections. Eventually the axons grow and migrate to their targets. This leads to the formation of a synapse. The synapses increase in number in the initial stage. The synapses that are used repeatedly mature and remain intact. However, most synapses are of no use and become inactive after forming. These synapses and the inactive neurons are removed by processes of synaptic pruning and neuronal death.

Thus, the given processes can be arranged in a temporal order as:

Proliferation -> Migration -> Aggregation -> Process Growth and Synapse Formation -> Neuronal Death