|Copyright: Kaustubh Wadekar (kaustubh0072) (54)|
|Date Taken: 2008-04-07|
|Camera: Nikon Coolpix S10|
|Exposure: f/3.5, 1/60 seconds|
|Details: (Fill) Flash: Yes|
|More Photo Info: [view]|
|Photo Version: Original Version|
|Date Submitted: 2008-07-29 23:47|
|[Note Guidelines] Photographer's Note|
|Jellyfish are marine invertebrates belonging to the class Scyphozoa of the phylum Cnidaria. They can be found in every ocean in the world and even in some fresh water. The name "jellyfish" is also applied to some close relatives of true scyphozoans, such as the Hydrozoa and the Cubozoa. Jellyfish live in groups called 'Bondamines'|
The body of a jellyfish consists of a bell shape producing jelly and enclosing its internal structure, from which tentacles are suspended. Each tentacle is covered with cells called cnidocytes, that can sting or kill other animals. Most jellyfish use these cells to secure prey or for defense. Others, such as the Rhizostomae, do not have tentacles at all.
Jellyfish lack basic sensory organs and a brain, but their nervous systems and rhopalia allow them to perceive stimuli, such as light and odour, and respond quickly. They feed on small fish and zooplankton that become caught in their tentacles. Most jellyfish are passive drifters and slow swimmers, as their shape is not hydrodynamic. Instead, they move so as to create a current forcing the prey within reach of their tentacles. They do this by rhythmically opening and closing their bell-like body. Their digestive system is incomplete: the same orifice is used to take in food and expel waste. The body of an adult is made up of 94–98% water. The bell consists of a layer of epidermis, gastrodermis, and a thick, intervening layer called mesoglea that produces most of the jelly.
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- [2008-07-30 3:32]
These jelly fish are very good to see Kaustubh. And interesting notes too - thank you.
You have captured them well - as it isn't easy through the glass of the aquarium