Cnidaria

Cosma / Communication / Knowledge / Realm / Terrestrial / Life / Animal / Invertebrate / Cnidaria

—————————

Introduction1

Dictionary

cnidaria : a phylum of more or less radially symmetrical invertebrate animals that lack a true body cavity, possess tentacles studded with nematocysts, and include the hydroids, jellyfishes, sea anemones, and corals — Webster   See also   OneLook

Thesaurus

Roget’s II (Thesaurus.com), Merriam-Webster Thesaurus, Visuwords

Encyclopedia

Cnidaria is a phylum under kingdom Animalia containing over 11,000 species of aquatic animals found both in freshwater and marine environments, predominantly the latter. Their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey. Their bodies consist of mesoglea, a non-living jelly-like substance, sandwiched between two layers of epithelium that are mostly one cell thick.

Cnidarians mostly have two basic body forms: swimming medusae and sessile polyps, both of which are radially symmetrical with mouths surrounded by tentacles that bear cnidocytes. Both forms have a single orifice and body cavity that are used for digestion and respiration. Many cnidarian species produce colonies that are single organisms composed of medusa-like or polyp-like zooids, or both (hence they are trimorphic). Cnidarians’ activities are coordinated by a decentralized nerve net and simple receptors. Several free-swimming species of Cubozoa and Scyphozoa possess balance-sensing statocysts, and some have simple eyes. Cnidarians are classified into four main groups: the almost wholly sessile Anthozoa (sea anemones, corals, sea pens); swimming Scyphozoa (jellyfish); Cubozoa (box jellies); and Hydrozoa (a diverse group that includes all the freshwater cnidarians as well as many marine forms, and has both sessile members, such as Hydra, and colonial swimmers, such as the Portuguese Man o’ War). Staurozoa have recently been recognised as a class in their own right rather than a sub-group of Scyphozoa. — Wikipedia

Cnidaria (Encyclopædia Britannica)

———————-

Innovation

Science

Biology is the scientific study of life. Biologists study life at multiple levels of organization, from the molecular biology of a cell to the anatomy and physiology of plants and animals, and evolution of populations. Biologists also study and classify the various forms of life, from prokaryotic organisms such as archaea and bacteria to eukaryotic organisms such as protists, fungi, plants, and animals. — Wikipedia

————————–

Preservation

Library

Subject: Cnidaria (WorldCat)

—————————

Participation

Education

MERLOT: Multimedia Educational Resource for Learning and Online Teaching
OER Commons: Open Educational Resources

Community

Occupation

Zoologists and Wildlife Biologists (CareerOneStop, U.S. Department of Labor, Employment and Training Administration)

Organization

American Institute of Biological Sciences

News

BioScience (American Institute of Biological Sciences)
Cnidaria (EurekaAlert, American Association for the Advancement of Science)
Cnidaria (Phys.org)
Cnidaria (Science News)
Cnidaria (NPR Archives)

Government

Document

Cnidaria (USA.gov)

——–
Related

Here are links to pages about closely related subjects.

Knowledge Realm

Terrestrial   (Earth)

Sphere Land, Ice, Water (Ocean), Air, Life (Cell, Gene)
Ecosystem Forest, Grassland, Desert, Arctic, Aquatic

Tree of Life
Microorganism Virus
Prokaryote Archaea, Bacteria
Eukaryote Protist, Fungi, Algae, Protozoa (Tardigrade)
Plant Flower, Tree
Animal
Invertebrate
Cnidaria Coral, Jellyfish
Cephalopod Cuttlefish, Octopus
Crustacean Lobster, Shrimp
Arachnid Spider, Scorpion
Insect Ant, Bee, Beetle, Butterfly
Vertebrate
Fish Seahorse, Ray, Shark
Amphibian Frog, Salamander
Reptile Turtle, Tortoise, Dinosaur
Bird Penguin, Ostrich, Owl, Crow, Parrot
Mammal Platypus, Bat, Mouse, Rabbit, Goat, Giraffe, Camel, Horse, Elephant, Mammoth
Walrus, Seal, Polar Bear, Bear, Panda, Cat, Tiger, Lion, Dog, Wolf
Cetacean Whale, Dolphin
Primate Monkey, Chimpanzee, Human

——
Notes

1.   The resources on this page are are organized by a classification scheme developed exclusively for Cosma.