Phylum CNIDARIA
The basics
Body Plans: Cnidarians have radial symmetry. Adults usually appear as swimming medusa or sessile polyps. Their ends are described as "Oral" (end nearest the mouth) and "aboral" ,(end furthest from the mouth.) All Cnidarians have stinging tentacles to subdue prey.
Habitat: All Cnidarians live in the ocean. They are abundant in shallow and deep waters. Cnidarians like the jellyfish are free-floating. Others, like the coral, are anchored to hard surfaces in adulthood. They live in every hemisphere of the planet.
Feeding: All cnidarians are carnivores. They use cnidae (toxins) to kill their food. Cnidarians don't actively hunt, instead simply float around or remain sessile until prey brush against their tentacles, which are then paralyzed because of the toxins in the tentacles. They eat shrimp, plankton, amphipods, fish and other organisms.
Reproduction: Cnidarians can reproduce sexually and asexually. Most polyps reproduce asexually by cloning themselves via fragmentation.. Medusaes can reproduce sexually externally by releasing clouds of eggs and sperm.
Habitat: All Cnidarians live in the ocean. They are abundant in shallow and deep waters. Cnidarians like the jellyfish are free-floating. Others, like the coral, are anchored to hard surfaces in adulthood. They live in every hemisphere of the planet.
Feeding: All cnidarians are carnivores. They use cnidae (toxins) to kill their food. Cnidarians don't actively hunt, instead simply float around or remain sessile until prey brush against their tentacles, which are then paralyzed because of the toxins in the tentacles. They eat shrimp, plankton, amphipods, fish and other organisms.
Reproduction: Cnidarians can reproduce sexually and asexually. Most polyps reproduce asexually by cloning themselves via fragmentation.. Medusaes can reproduce sexually externally by releasing clouds of eggs and sperm.
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WOW!There are over 10,000 species of cnidarians!
The greek word "cnidos" means stinging nettle! They have nerve impulses but no brain! They can weight up to several tons! A group of jellyfish is called a smack! The firing of nematocysts are the fastest reactions in the animal kingdom! Jellyfish are made up of more than 95% water! |
WANT TO LEARN MORE?
- http://animaldiversity.ummz.umich.edu/accounts/Cnidaria/
- http://www.google.ca/url?sa=t&rct=j&q=&esrc=s&source=web&cd=4&sqi=2&ved=0CD8QFjAD&url=http%3A%2F%2Feol.org%2Fpages%2F1745%2Foverview&ei=L7NeU4THHMPPlAXpl4CQBQ&usg=AFQjCNEqwrnGZL6hGCiDmstS2cEE_i62OQ&bvm=bv.65397613,d.aWw
- http://www.oceanicresearch.org/education/wonders/cnidarian.html