The nervous system is composed of two main cell types: Neurons and Glial cells.
Neurons are the main type of cell in the nervous system that generate and transmit electrochemical signals. They primarily communicate with each other using neurotransmitters at specific junctions called synapses. Neurons come in many shapes that often relate to their function, but most share three main structures: axons and dendrites extending out from a cell body.
The glial cells comprise astrocytes, oligodendrocytes, microglia, and ependymal cells in the central nervous system; satellite and Schwann cells in the peripheral nervous system. Their main functions include synaptic ion and pH homeostasis, blood-brain barrier maintenance, and structural support to neurons.
Neurogenesis is the process of neural development from the neural stem cells during embryonic development and adulthood. Neural stem cells divide and develop into mature neurons during neurogenesis.