Gourt > Kids and Teens > School Time > Science > Living Things > Animals > Invertebrates > Jellyfish
Jellyfish are marine invertebrates belonging to the Scyphozoan class, and in turn the phylum Cnidaria. The body of an adult jellyfish is composed of a bell-shaped, jellylike substance enclosing its internal structure, from which the creature's tentacles suspend. Each tentacle is covered with stinging cells (cnidocytes) that can stun or kill other animals: most jellyfish use them to secure prey or as a defense mechanism. Others, such as Rhizostomae, do not have tentacles at all. To compensate for its lack of basic sensory organs and a brain, the jellyfish exploits its nervous system and rhopalia to perceive stimuli, such as light or odor, and orchestrate expedient responses. In its adult form, it is composed of 94-98% water and can be found in every pelagic area of the world.
Most jellyfish are passive drifters that feed on small fish and zooplankton that become caught in their tentacles. Jellyfish have an incomplete digestive system, meaning that the same orifice is used for both food intake and waste expulsion. They are made up of a layer of epidermis, gastrodermis, and a thick jellylike layer called mesoglea that separates the epidermis from the gastrodermis.
Their shape is not hydrodynamic, which makes them slow swimmers. But speed and low water resistance are not important as they are drifters that feed on plankton. It is more important for them that their movements create a current where the water (which contains their food) is being forced within reach of their tentacles. They accomplish this by having a body shaped like a bell which is rhythmically opened and closed.
More on [ Jellyfish ]
ive said it for years. irukandji jellyfish are no friggin joke http://fwd4.me/7PN
willward1 (Will Ward) Tue, 08 Dec 2009 02:50:21 -0000
ive said it for years. irukandji jellyfish are no friggin joke http://fwd4.me/7PN
RT @vermontaigne: Half-inch jellyfish nearly kills man http://bit.ly/5j1CzX (via feedly) SCARY!
IdaFlo (Flo Johnson) Tue, 08 Dec 2009 02:49:50 -0000
RT @vermontaigne: Half-inch jellyfish nearly kills man http://bit.ly/5j1CzX (via feedly) SCARY!
I swim here too... this is how bad the stingers are... http://www.heraldsun.com.au/news/breaking-news/jellyfish-sting-victim-in-intens...
JuliaGates (Julia Gates) Tue, 08 Dec 2009 02:41:27 -0000
I swim here too... this is how bad the stingers are... http://www.heraldsun.com.au/news/breaking-news/jellyfish-sting-victim-in-intens...
Half-inch jellyfish nearly kills man http://bit.ly/5j1CzX (via feedly)
vermontaigne (Dan Collins) Tue, 08 Dec 2009 02:36:28 -0000
Half-inch jellyfish nearly kills man http://bit.ly/5j1CzX (via feedly)
What a PUSSY! RT @BoingBoing Half-inch jellyfish nearly kills man http://bit.ly/6LQOH4
beautifulkind (The Beautiful Kind) Tue, 08 Dec 2009 02:27:21 -0000
What a PUSSY! RT @BoingBoing Half-inch jellyfish nearly kills man http://bit.ly/6LQOH4
Giant Jellyfish Have Invaded Japanese Waters, Throwing The Fishing Industry Into Jeopardy -- Sky News http://bit.ly/83xXp8
barugboog (John Javellana) Tue, 08 Dec 2009 02:21:09 -0000
Giant Jellyfish Have Invaded Japanese Waters, Throwing The Fishing Industry Into Jeopardy -- Sky News http://bit.ly/83xXp8
Aquafacts: Jellies - Natural history information from the Vancouver Aquarium Marine Science Centre.
Aurelia Aurita (Saucer Jelly, Moon Jelly, Common Sea Jelly) - Contains information such as habitat, food habits, and behavior of the Moon Jelly.
Freshwater Jellyfish - Tells what the freshwater species, Craspedacusta sowerbii, looks like, where it lives, what it eats, and how it compares to its saltwater cousins.
Meta Description: [ A site about the freshwater medusa, Craspedacusta sowerbii. ]
Giant Jellyfish - Provides some basic information about jellyfish.
Glossary of Jellyfish - A guide to jellyfish found more commonly in the Gulf of Mexico.
Jellyfish - Printable chart and fact sheet show the life cycle of the jellyfish. From EnchantedLearning.com.
Meta Description: [ Jellyfish are invertebrates that live in the seas. ]
Jellyfish - Includes basic information about what to do if you are unlucky enough to encounter the tentacles of a jellyfish.
Jellyfish Up Close - A student's report on these creatures.
Jewels of the Sea - Virtual exhibit from the Oregon Coast Aquarium provides information about the anatomy, life span, and relatives of the jellyfish. Also includes streaming footage from the Aquarium's JellyCam.
Neither Jelly nor Fish - Article provides information about the stinging jellyfish which makes the Chesapeake Bay so inhospitable in the summer. Includes tips for preventing and treating stings, as well as a look at some of the problems with controlling the population.
Meta Description: [ Each summer, flotillas of sea nettles invade the Chesapeake Bay. By July they have often grown so thick in the Bay's creeks, rivers and open waters that bathers begin an annual evacuation of the water. Not so for scientists. Stinging nettles and other gelatinous zooplankton have been enticing res... ]
Scyphozoan Jellyfish Basics - Lists details such as the structure, life cycle, and life span of jellyfish.
Meta Description: [ Jellyfish aquarium, stand, canopy, filter or custom acrylic tanks for sale ]
Sea Science Series: Jellyfish - Diagrams and text show the anatomy of the jellyfish and its lifecycle, as well as several common species. From the South Carolina Department of Natural Resources.
Something's Lurking in the Sea - Tells how jellyfish sting and provides tips for those unfortunate enough to encounter the creature's tentacles.
Swimmers Beware: Jellyfish are Everywhere - Article from National Geographic World tells about jellyfish and the danger they pose. Includes tips for avoiding stings.
Meta Description: [ Beware of jellyfish when swimming. Learn fast facts about these sea creatures and how to avoid being stung. A colorful diagram shows the different parts of the jellyfish. ]
The Appalachian Mountain Jellyfish - Explains the appearance, life cycle, and feeding habits of the freshwater jellyfish.
The Bluebottle or Portuguese Man-of-War - Offers information about the Portuguese Man-of-War and some helpful tips if you are unlucky enough to be stung by one.
Meta Description: [ The Bluebottle or Portuguese Man-of-War is not a single animal but a colony of four kinds of highly modified individuals (polyps). ]
The Box Jellyfish - Provides information about the deadliest sea creature.
| Jellyfish | |
| Next Video | |
