Bioluminescence is the production and emission of light by a living organism. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some fungi, microorganisms including some bioluminescent bacteria, and terrestrial arthropods such as fireflies. In some animals, the light is bacteriogenic, produced by symbiotic bacteria such as those from the genus Vibrio; in others, it is autogenic, produced by the animals themselves.
In a general sense, the principal chemical reaction in bioluminescence involves a light-emitting molecule and an enzyme, generally called luciferin and luciferase, respectively. Because these are generic names, luciferins and luciferases are often distinguished by including the species or group, e.g. firefly luciferin. In all characterized cases, the enzyme catalyzes the oxidation of the luciferin. In some species, the luciferase requires other cofactors, such as calcium or magnesium ions, and sometimes also the energy-carrying molecule adenosine triphosphate (ATP). Conversely, luciferases vary widely between different species The phenomenon is widely distributed among animal groups, especially in marine environments. On land it occurs in fungi, bacteria and some groups of invertebrates, including insects. Bioluminescence is a form of chemiluminescence where light energy is released by a chemical reaction. This reaction involves a light-emitting pigment, the luciferin, and a luciferase, the enzyme component.
In Simple: Luciferin + O2---------------Oxyluciferin + light energy
Coelenterazine is a luciferin found in many different marine phyla from comb jellies to vertebrates. Like all luciferins, it is oxidised to produce light. Instead of a luciferase, the jellyfish Aequorea victoria makes use of another type of protein called a photoprotein, in this case specifically aequorin luciferase enzymes vary widely and tend to be different in each species.
Distribution in Nature:
Bioluminescence occurs widely among animals, especially in the open sea, including fish, jellyfish, comb jellies, crustaceans, and cephalopod molluscs; in some fungi and bacteria; and in various terrestrial invertebrates including insects. About 76% of the main taxa of deep-sea animals produce light. Most marine light-emission is in the blue and green light spectrum. However, some loose-jawed fish emit red and infrared light, and the genus Tomopteris emits yellow light.
The most frequently encountered bioluminescent organisms may be the dinoflagellates in the surface layers of the sea, which are responsible for the sparkling phosphorescence sometimes seen at night in disturbed water.
Non-marine bioluminescence is less widely distributed, the two best-known cases being in fireflies and glowworms, bioluminescent beetle Elateroidea
Invertebrates including insect larvae, annelids and arachnids possess bioluminescent abilities.
Bacterial symbiose: Organisms often produce bioluminescence themselves, rarely do they generate it from outside phenomena. However, there are occasions where bioluminescence is produced by bacterial symbionts that have a symbiotic relationship with the host organism. Although many luminous bacteria in the marine environment are free-living, a majority are found in symbiotic relationships that involve fish, squids, crustaceans etc. as hosts. Most luminous bacterial inhabit the marine sea.
Who glows?????
At least 1,500 species of fish are known to be bioluminescent, including sharks and dragonfish—and scientists regularly discover new ones. It occurs most commonly in the ocean, where bioluminescence is often the only source of light. A whopping 76 percent of ocean animals are bioluminescent, which means they produce their own light through a series of chemical reactions.
Uses in nature: Bioluminescence is used in a variety of ways and for different purposes.
Bioluminescence has several functions in different taxa. : defensive functions of startle, counter-illumination (camouflage), misdirection (smoke screen), distractive body parts, burglar alarm (making predators easier for higher predators to see), and warning to deter settlers; offensive functions of lure, stun or confuse prey, illuminate prey, and mate attraction/recognition. The Followings are some points:
i) COUNTER-ILLUMINATION: In many animals of the deep sea, including several squid species, bacterial bioluminescence is used for camouflage by counter-illumination, in which the animal matches the overhead environmental light as seen from below. Example in firefly squid, Watasenia scintillans. (When seen from below by a predator, the bioluminescence helps to match the squid's brightness and color to the sea surface above.)
ii) DEFENSE & SURPRISE: The prey produces a bright flash that startles a predator, making it easy to escape.
iii) SMOKE SCREEN: The prey emits a glowing fluid or a cloud of sparks to misdirect the predator from its real location.
iv) DECOY: The prey jettisons one of its body parts. The luminescent limb distracts the predator, allowing escape.
v) CAMOUFLAGE: A shining underbelly matching the light from the surface conceals prey from predators below. Hawaiian bobtail squid light up via bioluminescent bacteria living in one of their organs; the light camouflages them against moonlight on the surface and eliminates their shadow, obscuring them from predators.
vi) ALARM: The prey’s bioluminescence makes its predator visible—alerting the predator’s predators.
vii) OFFENSE: Among the most iconic are deep-sea fishes like the anglerfish, whose females sport a lure of glowing flesh that acts as bait for any prey close enough to be snatched.
viii) SHOCK:A burst of bright light from a bioluminescent predator stuns prey and leaves it open to attack.
ix) LURE: Like a moth to a flame, prey is drawn to the glow produced by a predator lurking all too close.
x) BEACON: Predators seek out the glimmer that tells them that bioluminescent creatures are gathering.
xi) SEARCHLIGHT: A predator turns on its natural spotlight to locate prey in a dark ocean.
xii) REPRODUCTION: Flickers of light signal that a bioluminescent insect is ready to meet new mates. In the marine environment, use of luminescence for mate attraction is chiefly known among ostracods, small shrimplike crustaceans, especially in the family Cyprididae. Fireflies use light to attract mates. Two systems are involved according to species; in one, females emit light from their abdomens to attract males; in the other, flying males emit signals to which the sometimes sedentary females respond.
xiii) INVITATION: Mushrooms may spread their spores by using luminescence to entice insects to land on them.
Freshwater animals Doesnot glow because Very few bioluminescent fish can tolerate low salinity
Some species of dinoflagellates light up using a similar to chemical reaction to that of fireflies; both use a naturally occurring molecule called luciferin, named for Lucifer, the light-bearer. Millions of these one-celled organisms create a beautiful shimmering effect, particularly when there’s little moonlight. It is very beautiful to stare.
Charles Darwin noticed bioluminescence in the sea, describing it in his Journal:
While sailing in these latitudes on one very dark night, the sea presented a wonderful and most beautiful spectacle. There was a fresh breeze, and every part of the surface, which during the day is seen as foam, now glowed with a pale light. The vessel drove before her bows two billows of liquid phosphorus, and in her wake she was followed by a milky train. As far as the eye reached, the crest of every wave was bright, and the sky above the horizon, from the reflected glare of these livid flames, was not so utterly obscure, as over the rest of the heavens.
"Let Pictures tell the beauty of Nature"--------Sahidul
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| Beauty Of Glowing Dinoflagellets at Night |
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| The Firefly |
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| Glowing Jellyfishes |
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| Glowing Mushrooms |
("NATURE WAS CREATED SO BEAUTIFUL THAT THERE IS ENDLESS MYSTERY IN IT"~ Sahidul)
Authored, Written And Presented By: Sahidul Islam On The 14th Nov, 2020 (https:vetuniverse.blogspot.com)
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