phototropism


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phototropism

 [fo-tot´ro-pizm]
1. tropism of an organism in response to light; it may be either positive (toward the light) or negative (away from the light).
2. change of color produced in a substance by the action of light. adj., adj phototrop´ic.

pho·tot·ro·pism

(fō-tot'rō-pizm),
Movement of a part of an organism toward (positive phototropism) or away from (negative phototropism) the stimulus of light. Compare: phototaxis.
[photo- + G. tropē, a turning]

phototropism

(fō-tŏt′rə-pĭz′əm, fō′tō-trō′-)
n.
Growth or movement of a sessile organism toward or away from a source of light.

pho′to·tro′pic (fō′tə-trō′pĭk) adj.

pho·tot·ro·pism

(fō-tot'rŏ-pizm)
Movement of a part of an organism toward (positive phototropism) or away from (negative phototropism) the stimulus of light.
Compare: phototaxis
[photo- + G. tropē, a turning]

phototropism

a bending growth movement of parts of a plant in response to a light stimulus. The movement produced by unequal growth is due to differences in AUXIN concentration. For example, most seedlings are positively phototropic, growing towards a light stimulus, because there is a greater concentration of auxin on the side furthest away from the light, giving greater growth on this side. Roots, on the other hand, are often negatively phototropic, growing away from a light source.

phototropism 

Reaction of certain plants and animals to move towards (positive phototropism) or away from (negative phototropism) a source of light.
References in periodicals archive ?
It was found that when several of the PIN and kinase components were missing, plant growth was completely unresponsive to the light signals that trigger phototropism. The auxin transport mechanism in these mutant plants was severely impaired: The plants grew upwards, away from the gravitational pull, irrespective of the light source.
Plant responses to light include amount and direction of growth and development as well as timing and amount of flowering, color development in fruit, and plant movements, or phototropisms.
Phototropism is the influence of varying durations of light on plant growth and development.
When a cut flower curves or bends in the direction of light, as do anemones, this phenomenon is specifically called phototropism, from the Greek words photo (light) and trope (turning).
phototropism. Turning or bending in response to light.
See Photosynthesis, Phototropism. (2) To become ignited; to take fire.
hiddoside = gene (from hiddo = origin + side = carrier) ilaysraac = phototropism (to follow light) kaadisokorow = diabetes (sugared urine) iidheh = advertising (to say for me) kulbeeg = thermometer (hot measurement) hantidhowr = finance court (control of wealth) ilmaqabato = microscope (not seen by the eye) dayaxgacmeed = man-made satellite (hand-size moon) xeerilaaliye = state prosecutor (guardian of the law) Other neologisms, which were not possible to form from Somali, are made up of words borrowed from the three foreign languages that are widespread in the country (Italian, English, and Arabic).
urchins showed a heightened negative phototropism in response to
Phototropism in the larval and early adolescent stages of Homarus americanus.
U tomentosa has a positive phototropism, and luminosity required for the development of younger individuals located in areas of natural regeneration (CANALES-SPRINGETT et al., 2013a).
(2005) found that pediveligers of the variegated scallop Chlamys varia had positive phototropism. Christophersen and Magnesen (2009) observed that light had no effect on larval settlement of the king scallop, Pecten maximus.
Auxin is the first plant hormone studied and it has been correlated with several developmental processes like root initiation, apical dominance, plant growth, geotropism and phototropism and fruit development (Paciorek & Friml, 2006).