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Jellyfish


Jellyfish
Photo Information
Copyright: jessica balderas (jessbalderas) Silver Note Writer [C: 5 W: 0 N: 12] (54)
Genre: Animals
Medium: Color
Date Taken: 2006-08-06
Categories: Crustacia
Camera: Sony Cybershot DSC P7
Exposure: f/3.5, 1/15 seconds
More Photo Info: [view]
Photo Version: Original Version
Date Submitted: 2007-10-29 9:35
Viewed: 5160
Points: 4
[Note Guidelines] Photographer's Note
Jellyfish are marine invertebrates belonging to the Class Scyphozoa within the Phylum Cnidaria. They can be found in every ocean in the world. The use of the term "jellyfish" is actually a misnomer since scyphozoans are not fish, which are vertebrates. The term is also (incorrectly) commonly-applied to some close relatives of true scyphozoans, such as the Hydrozoa and the Cubozoa.

The body of an adult 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 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 odor, 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, and the bell shape consists of a layer of epidermis, gastrodermis, and a thick layer called mesoglea that produces most of the jelly and separates the epidermis from the gastrodermis.

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Critiques [Translate]

Original y diferente a lo común que vemos cada dia. Algo justa de enfoque.

Un abrazo Jessica: J. Ignasi

  • Great 
  • mokina (11)
  • [2007-10-31 16:53]

Hallo Jessica,
excellent shot, with great colours and good composition!

Thank's for visit :D

Ciao
Mokina

  •      
  • Lycaon Silver Star Critiquer [C: 45 W: 7 N: 31] (114)
  • [2008-06-28 14:49]

Hi. Not Crustacea, but Cnidaria. Please recategorize.

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