Signal (biology)

A signal in biology is any kind of coded message sent from one organism to another, or from one place in an organism to another place.

Vocal calls
Some social behaviours
Chemical signals 
inside organisms
nerve transmission
hormones
inside cells
between organisms

In biology, especially in electrophysiology, a signal or biopotential is an electric quantity (voltage or current or field strength), that is caused by chemical reactions of charged ions. Biological signals can also be seen as an example of signal (electrical engineering).

Another use of the term lies in the transfer of information between and within cells, as in signal transduction. 

Related pages
 Signal transduction

Category:Physiology
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