phototaxis

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Related to phototactic: Phonotactic

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 ?
Phototactic behavior: repellent effects of cigarette beetle, Lasioderma serricorne (Coleoptera: Anobiidae), to light-emitting diodes.
In addition, the phototactic response of larval and juvenile fishes may be lower at lower light intensities (Gehrke, 1994; Stearns et al., 1994).
We found that the control comb jelly was able to compensate for the disorienting effects of altered gravity by using its phototactic ability.
The positive relationship between density and percent cloud cover may have been a phototactic response to decreasing light conditions.
A note on phototactic behaviour and on phoretic associations in larvae of Mecistogaster ornata Rambur from northern Costa Rica (Zygoptera: Pseudostigmatidae).
Live zooplankters (principally copepods) for isotopic analysis were separated from suspended detritus by settling and decanting, or by phototactic concentration.
Phototactic behavior in the absence of fish kairomone as well as the change in phototactic behavior in response to the presence of fish kairomone are studied.
The larvae of both species of Antipathes in Hawaii are known to be negatively phototactic which explains why they are not found at shallow depths (< 30 m) and are most abundant beneath overhangs and on other dimly lit surfaces (Grigg, 1965).
Consistent with this finding, adult Limulus exhibit a positive phototactic response when their MEs are illuminated with UV light but no response when their MEs are illuminated with visible light.
Observations of the fly in the field strongly suggest it is positively phototactic, as during mornings more flies are usually seen at sunlit than shady sides of trees (Frick et al.
If pelagic larvae are positively phototactic and become negatively phototactic during the settlement stage it is likely that light conditions would have had an influence on [??][O.sub.2], as has been shown for juvenile individuals (Ahmed et al.
Phototactic Responses of Larvae from the Marine Sponge Xestospongia proxima.