When conducting hygienic research, an urgent task is to search for simple multicellular animals with social behavior to solve the fundamental issues of the interaction of cells with destabilizing environmental factors. Such factors include the light environment, which controls the biological clock of living organisms through the spectral composition of the light spectrum. Light through the system of ganglion cells of the eyes and the pineal gland with its "serotonin-melatonin" system controls the" circadian rhythms" of a person. The pineal gland in its structure has a spatial distribution of CaCO3 microcrystals, serotonin and melatonin synthesis cells from tryptophan, as well as a neuropeptide network. The search for a modal animal for the study and modeling of processes in the human pineal gland is an urgent hygienic task. Such a model animal can become a marine animal Trichoplax (Placozoa) has the simplest organization among all known animals with only six distinguishable cell types, but with outstanding social behavior. The theoretical analysis of the spectral composition of light and the degree of its polarization in the marine environment of the simplest multicellular animal Trichoplax (Placozoa), as well as the features of its gene-cell structure, is carried out. Based on the laws of hydrooptics and the survival strategy ("food-prey"), the coordinate axes of the light medium for Trichoplax are determined (the light vertical (395 nm) and two horizontal light axes - the reflected horizontal light from the food (green - 532 nm) and the fluorescent light coming from the aragonite shell of the predator mollusk (red - 630 nm). Based on the animal's reactions to these RGB light stimuli, a hypothesis is made about the presence of an RGB taxis in Trichoplax. The monochrome light signals red - 630 nm, green - 532 nm and blue - 395 nm are selected for Trichoplax control. Experimentally, within the framework of the work "Trichoplax for Bionics", the discovery of an RGB taxi in Trichoplax was confirmed. Trichoplax Movement control RGB -taxsis - YouTube
light stimuli, Trichoplax, crystal cells, aragonite, pineal gland, calcite crystals, phototaxis, tryptophan, serotonin, neuropeptide network, circadian rhythms
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