Nervous Tissue: NeuronsNervous tissue is responsible for sensing stimuli and transmitting signals to and from different parts of an organism. Neurons are the basic unit of nervous tissue.
As we have previously discussed, structure and function are very much intertwined within biology and the structure of a neuron is uniquely suited to its function within nervous tissue.
A neuron consists of two major parts:
The central cell body contains the neuron's nucleus, associated cytoplasm, and other organelles.
- Nerve Processes
Nerve processes are "finger-like" projections from the cell body that are able to conduct and transmit signals. There are two types:
Axons - typically carry signals away from the cell body.
Dendrites - typically carry signals toward the cell body.
Unlike axons, dendrites are usually more numerous, shorter and more branched. As with other structures in organisms, there are exceptions.
Bundles of axons and dendrites are called nerves. They are sensory if they consist of dendrites only, motor if they consist of axons only and mixed if they consist of both.