He phototaxis or phototaxis is a reaction of the cellular organisms to the luminous stimuli. It can be of two types, depending on the reaction of the organism to light: positive, when it approaches it; negative, when you move away from it.
An example of positive phototaxis or phototaxis is that of mosquitoes, flies or moths. Especially in summer, when their presence is greater, they tend to look for natural light or artificial light bulbs, for example - and fly around them.
Phototaxis is related to the reaction of cells to light stimuli
On the contrary, other insects like the cockroaches flee of the light, being an example of negative phototaxis.
Phototaxis in photosynthetic living beings
Phototaxis or phototaxis also affects plants. They need light to perform photosynthesis, the process necessary for their development.
Therefore, they tend to grow looking for greater exposure to sunlight. The leaves of the plants make this movement, while the roots always grow against the sunlight.
These directional and growth movements caused by sunlight have a certain internal complexity.
Science studies and explains them as part of the vital processes of plants. Thus, plants receive sunlight through blue wavelength receptors - known as phototropin 1 and 2 -.
There the phosphorylation of the proteins, which will trigger the subsequent growth and movement of the plants towards the light.
Phototaxis in insects and other living things
As we explained earlier, not all insects seek light; some flee from it - negative phototaxis.
In the first case, living beings accustomed to using natural light Moon and stars, for example - to get their bearings.
When they perceive an artificial light source - a spotlight, a bulb, etc. - tend to approach it. The most obvious example is mosquitoes fluttering around the house lamps when the rest of the room is in darkness.
In contrast, insects lucrifers are those who flee from the light. For example, cockroaches.
These living beings react against light stimuli by not being typical of their habitats and consider them a threat to their survival.
The impact of phototaxis on human life
Knowing the phenomenon of phototaxis or phototaxis is useful for humans. In the case, for example, of fishing, the reaction of fish to the presence of light - they tend to approach the light and swim towards it - is used by fishermen.
Thus, the use of artificial light is a support technique to increase the volume of the catches.
On the other hand, when it comes to insects, the use of special lights can decrease the presence of insects around them.
Thus, it is possible to reduce the presence of mosquitoes during summer nights and avoid pitting. In the case of cockroaches, light can be useful to ward off them. As we have seen, they escape the light -phototaxia negative- when they feel threatened by it.
References
- Phototaxism. Department of Plant Biology, Carnegie Science Carnegie Science. Ed.
- Judith P. Armitage & Klaas J. Hellingwerf, 'Light-induced behavioral responses (' phototaxis ') in prokaryotes'. (2003). Kluwer Academic Publishers, Netherlands.
- Why are bugs attracted to light?, iflscience.com.
- 'Plant Responses to Light: Phototaxis, Photomorphogenesis, and Photoperiodism'. Botany on-line 1996-2004 at biologie.uni-hamburg.de.
'Photophysiology: General Principles; Action of Light on Plants'. Edited by Arthur C. Giese. (1964). Academic Press New York & London.