Introduction

A bioluminescent Jellyfish
Image Source

What if we have our own source of light that we may never come to think about where to look for a source?

What if we want to travel amidst the night? Or else we want to voyage? What could be our source of light which can lit our way to reach towards our destination? But what if we ourselves exhibit a very own characteristic which could light our sight in order to settle in the night? It would be very cool that humans could have an extraordinary characteristic that will make us unique from other creatures but it couldn't be possible since humans are already created this way.

Though humans can't create our own light, some animals do, in a process called bioluminescence. Fireflies are perhaps the best known example, though many other species are bioluminescent, including glow worms, anglerfish, and octopus. Even some plants, such as mushrooms and other fungi, are bioluminescent.

This blog offers you an information about the process of self-exhibition called Bioluminescence which is partially discussed above. This also offers an insight about how bioluminescence is exhibited and what elements are present in an organism that could be used to illuminate and exhibit their own light.

What is Bioluminescence?

Bioluminescence is the production and emission of light by a living organism as the result of a chemical reaction during which chemical energy is converted to light energy.

Bioluminescence is a "cold light." Cold light means less than 20% of the light generates thermal radiation, or heat.

How is it produced?

Bioluminenscent Bay of Planktons
Image Source

Most bioluminescent organisms are found in the ocean. These bioluminescent marine species include fish, bacteria, and jellies. Some bioluminescent organisms, including fireflies and fungi, are found on land. There are almost no bioluminescent organisms native to freshwater habitats.

The Chemistry Side

The chemical reaction that results in bioluminescence requires two unique chemicals: luciferin and either luciferase or photoprotein. Luciferin is the compound that actually produces light. In a chemical reaction, luciferin is called the substrate. The bioluminescent color (yellow in fireflies, greenish in lanternfish) is a result of the arrangement of luciferin molecules.

Luciferase is an enzyme. An enzyme is a chemical (called a catalyst) that interacts with a substrate to affect the rate of a chemical reaction. The interaction of the luciferase with oxidized (oxygen-added) luciferin creates a byproduct, called oxyluciferin. More importantly, the chemical reaction creates light.

Bioluminescent organisms can glow in complete darkness. They contain a unique compound called luciferin, according to scientists who study bioluminescence at the University of California at Santa Barbara. When luciferin is exposed to oxygen, a chemical reaction (aided along by an enzyme called luciferase) emits light.

Bioluminescence's Advantage to Species

A firefly, Photinus pyralis
Image courtesy of Terry Priest;
image source: Flickr

Bioluminescent Squid
Image Source

Bioluminescence – light produced by living organisms – is widespread in nature, but what advantage does it give the species that use it? In fact, there are many, including:

• Aposematism (toxic appearance) – to look inedible to potential predators.
  Example: the fireflies Photinus ignitus and Lucidata atra.
• Defence – to startle predators by emitting a bright flash at close range.
  Example: sternchasers, a type of myctophid or lanternfish.
• Courtship – to communicate before or during mating.
  Example: fireflies.
• Lures – to attract prey to the light source.
  Example: the angler fish.
• Camouflage – to help the animal to blend in with its background. As seen from below, a sea animal will look dark against the brightness of the water surface above, so producing its own light will help it to hide from potential predators.
  Example: squids such as Abralia verany.

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Angler Fish in its bioluminescence
Image Source

Bioluminescence has fascinated people for thousands of years and continues to be a popular subject of research, particularly in oceanic exploration projects. The chemical reactions that lead to the production of light by organisms are a great example of biochemistry.Perhaps the most spectacular bioluminescence displays come from dinoflagellate plankton, which cause the glowing blue waves sometimes seen on the ocean’s surface. More exotic forms of bioluminescence are found in the ocean depths; where there is no sunlight at all, many species make their own illumination. Famously, angler fish use a dangling light to lure their prey straight to their teeth.

References

1. https://www.livescience.com/32651-what-causes-bioluminescence-.html
2. http://www.scienceinschool.org/content/living-light-chemistry-bioluminescence
3. https://www.nationalgeographic.org/encyclopedia/bioluminescence/
4. https://www.sciencedaily.com/terms/bioluminescence.htm
5. Marie Walsh, Limerick Institute of Technology, Ireland
   Chemistry, Biology, Luminescence, Ecology

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