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The pollen grains reflect UV-beta to shield their chromosomes stored in the pollen from UV-alpha which is important for making sure of reproductive success. [10] The technique of UV coloration has evolved in other species as well for various reasons. Similarly, carnivorous plants reflect and absorb UV to attract prey to it. [10]
Photolyase is a phylogenetically old enzyme which is present and functional in many species, from the bacteria to the fungi to plants [9] and to the animals. [10] Photolyase is particularly important in repairing UV induced damage in plants.
Cyanobacteria photosystem II, dimer, PDB 2AXT. Photoinhibition occurs in all organisms capable of oxygenic photosynthesis, from vascular plants to cyanobacteria. [14] [15] In both plants and cyanobacteria, blue light causes photoinhibition more efficiently than other wavelengths of visible light, and all wavelengths of ultraviolet light are more efficient than wavelengths of visible light. [14]
In the average human adult it is estimated that 50 to 70 billion cells die each day from apoptosis. One of the largest promoters of apoptosis is exposure to ultraviolet (UV) light. While UV light is essential to human life it can also cause harm by inducing cancer, immunosuppression, photoaging, inflammation, and cell death. [1]
These secondary metabolites that provide plants with protection are commonly used in human sunscreen and pharmaceutical drugs to supplement the inadequate light protection that is innate to human skin cells. [9] Various pigments and compounds can be employed by plants as a form of UV photoprotection as well. [10]
DNA may be modified, either naturally or artificially, by a number of physical, chemical and biological agents, resulting in mutations. Hermann Muller found that "high temperatures" have the ability to mutate genes in the early 1920s, [2] and in 1927, demonstrated a causal link to mutation upon experimenting with an x-ray machine, noting phylogenetic changes when irradiating fruit flies with ...
Photoexcitation is the first step in a photochemical process where the reactant is elevated to a state of higher energy, an excited state.The first law of photochemistry, known as the Grotthuss–Draper law (for chemists Theodor Grotthuss and John W. Draper), states that light must be absorbed by a chemical substance in order for a photochemical reaction to take place.
Somaclonal variation is the variation seen in plants that have been produced by plant tissue culture. Chromosomal rearrangements are an important source of this variation. . The term somaclonal variation is a phenomenon of broad taxonomic occurrence, reported for species of different ploidy levels, and for outcrossing and inbreeding, vegetatively and seed propagated, and cultivated and non ...