Taxis

The word taxis can also be plural of taxi.

A taxis (plural taxes, pronounced "takseez") is an innate behavioural response to a directional stimulus (a stimulus from a particular direction) whereby the organism either moves toward (positive taxis) or away from (negative taxis) the stimulus, called orientation movement . For example, organisms in the genus of flagellate protozoa Euglena moves towards a light source. Here the directional stimulus is light, and the orientation movement is toward it. This is positive taxis to light, more specifically positive phototaxis .

Other forms of taxis include chemotaxis, mechanotaxis, haptotaxis and durotaxis.