Neuron cell body (soma) - magnified
Soma (pericaryon) neuronis
NervousNervesWhole body
- What it is
- Magnified model (about 1000x) of a multipolar neuron such as a spinal motor neuron. The cell body holds the nucleus, stacks of rough endoplasmic reticulum (Nissl bodies) and the machinery that makes the proteins for the whole cell.
- Function
- Keeps the entire neuron alive and integrates the signals arriving on its dendrites before firing an impulse from the axon hillock.
- Size
- Real soma 20-100 micrometres across; shown ~16 mm
- Clinical note
- Neurons do not divide, so a lost cell body is not replaced; motor neurone disease (ALS) destroys exactly these cells.