phototaxis


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phototaxis

 [fo″to-tak´sis]
taxis of cells and microorganisms under the influence of light. adj., adj phototac´tic.

pho·to·tax·is

(fō'tō-tak'sis),
Reaction of living protoplasm to the stimulus of light, involving bodily motion of the whole organism toward (positive phototaxis) or away from (negative phototaxis) the stimulus. Compare: phototropism.
[photo- + G. taxis, orderly arrangement]

phototaxis

(fō′tō-tăk′sĭs)
n.
The movement of an organism or a cell toward or away from a source of light.

pho′to·tac′tic (-tăk′tĭk) adj.
pho′to·tac′ti·cal·ly adv.

pho·to·tax·is

(fō'tō-tak'sis)
Reaction of living protoplasm to the stimulus of light, involving bodily motion of the whole organism toward (positive phototaxis) or away from (negative phototaxis) the stimulus.
Compare: phototropism
[photo- + G. taxis, orderly arrangement]

phototaxis

the movement of a whole organism in response to a directional light stimulus. For example, movement of unicellular algae or fruit flies towards a source of light is positive phototaxis, while movement away from light if the stimulus is too strong is negative phototaxis.
References in periodicals archive ?
Ontogeny of phototaxis and metamorphic competence in larvae of the nudibranch Phestilla sibogae Bergh (Gastropoda: Opisthobranchia).
imbecillis that had completed their parasitic phase with chironomids (what I referred to as post-chironomid larvae) exhibited negative phototaxis only in the presence of water that had been modified by U.
Spudich, "Two rhodopsins mediate phototaxis to low- and high-intensity light in Chlamydomonas reinhardtii," Proceedings of the National Academy of Sciences of the United States of America, vol.
Males have obvious phototaxis. The second generation of eggs begins to hatch in the middle of July, with pupation beginning in mid to late August and adult emergence in early September.
Lids sidewalls where covered with black tape to avoid phototaxis. Seven minutes after the introduction of the larvae, the number of individuals within a 30 mm radius from each filter disc and the larvae that remained between both 30 mm radius were counted.
Agents were evolved for goal seeking (phototaxis) task and their performance were tested in the presence of sensorimotor and structural perturbations and for different levels of neural noise during agent lifetime.
However, a common misunderstanding is that this attraction represents a positive phototaxis. Contrary to this belief, Thompson (1917), Verheijen (1958), Mazokhin-Porshnyakov (1969), Janzen (1983), and more recently Nowinszky (2003) observed that insect attraction to lights is the result of navigational confusion.
These orchids had adapted by pointing upward to seek sunlight (positive phototaxis) and opposing gravity.
Escape behavior mediated by negative phototaxis in the scorpion Paruroctonus utahensis (Scorpiones, Vaejovidae).
Both species use a statocyst to detect changes in gravity (geotaxis) and a photoreceptor to detect changes in light (phototaxis).