Neurons & Glia
Overview
- The brain comprises blood vessels and two main cell types: neurons and their supporting cells: glia. It comprises at least 100 billion neurons.
Neurons
2 Types:
- Pyramidal cells
- 10 to 80 micrometers (?m) in diameter and are shaped like a flask with a single thick, cortically oriented apical dendrite and multiple basal dendrites. One important pyramidal cell type is the Betz cell, which lies within the primary motor cortex.
- Non-pyramidal cells
- 5 to 15 ?m in diameter. The term non-pyramidal cell is used interchangeably with the terms stellate or granule cells. But other non-pyramidal cell types exist, which include basket cells, fusiform cells, Horizontal cells of Cajal, Martinotti cells, and neurogliaform cells.
Glia (aka neuroglia)
4 types:
- Astrocytes
- Microglia
- Oligodendrocytes
- Ependymal cells