Excitable Tissue and Bioelectric Signals

In living tissue, important communication control is implemented by hormones and nerves. Hormones are slow broadcasting information carriers nerves are quick prewired point-to-point information carriers. Some cells are not excitable, such as adipose, connective tissue, and blood. They are passive, not under nerve control, and only weakly polarized. However, nerve, muscle, and gland cells are polarized and excitable within a 1/1000 s, such cells may react on trigger signals. The excitation of a cell is accompanied by an action potential. The action potential is the basic bioelectric event and signal source in the body. 

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