Neurofilaments and Microtubules - Nervous System
The cell body constitutes the trophic apparatus of the neuron in which most biosynthetic activity occurs producing chemicals needed for other parts of the cell, for example, the axon. Rough endoplasmic reticulum is present in the cell body and dendrites but is absent in axon. Since rough endoplasmic reticulum is the principal protein-manufacturing machinery of the cell, the axon gets its proteins from the cell body. Movement of a large variety of substances from the perikaryon to and along the axon constitutes phenomenon of axonal transport. Extending throughout the cytoplasm from dendrites to the axon, are present fine fibrilar structures called neurofilaments and microtubules.