Category: Photobiology

This is a special application of the field of photobiology. Cell death can be induced in cancerous cells by making them photosensitive using a photosensitizing drug. This is referred to as photodynamic therapy where photons are used to treat a condition and it is not a recent event. The light source determines the effect of…

It also manifests the regulatory effects of light. Melanocytes synthesize melanin pigment responsible for skin color in humans. Melanin is synthesized by tyrosine oxidation and its polymerization. This reaction is mediated by light exposure. Prolonged exposure to the sun can increase melanin production.

It is the property by which living beings emit light. Organisms that show this property include Aequorea Victoria, dinoflagellates, firefly squid, and honey fungus. Luciferase enzyme is the photoprotein that catalyzes the biochemical reaction for the emission of light. Luciferin substrate is oxidized in the presence of this enzyme, which leads to its excitation and…

Organisms have an internal biological rhythm that is mediated by a biological clock synchronized by a diurnal rhythm. Animals exhibit certain behavioral patterns and certain physiological responses in a diurnal rhythm. For instance, in the daytime, the loa loa releases their microfilariae into the peripheral blood. Nocturnal organisms are active at night time while diurnal…

In this kind of tropism, biological entities like plants can respond to light stimuli. The response can be negative or positive based on the fact whether the organism moves or grows towards the light source or away from it. The shoots of plants demonstrate positive tropism as they grow towards the light to increase photosynthesis…

Light is an essential abiotic physical factor that directly and indirectly affects organisms and the surroundings they live in. Some organisms like photoautotrophs are dependent on light to derive their energy through photosynthesis and synthesize food. Thylakoid membranes have photosystems with pigments that are capable of extracting energy from photons and absorbing it. The absorbed…

Photobiology is a multidisciplinary subject with specialty areas. Photophysics focuses on the physical aspects of light as a wave and as a photon and studies its effect at atomic and molecular levels. Photochemistry specializes in the chemical molecular reaction that occurs after photon absorption.

This biology subdiscipline focuses on the biology of light. This discipline studies the effect of light and various factors associated with it like its duration and intensity and their effect on biological processes.