by: chelsey mcintosh

Jellyfish

By: Chelsey McIntosh

What are Jellyfish?Also known as jellies or sea jellies, jellyfish are free swimming marine invertebrates that are members of the phylum Cnidarian. They are jelly-like and almost transparent with a bell shaped body. Jellyfish generally have long stinging threads on the surface. They are among the largest planktonic animals, they feed mostly on zooplankton and small fish. Some jellyfish can grow as large as 2 meters in diameter, with tentacles much longer.

Characteristics of the Phylum Cnidarian

They have radial symmetry blind sac gut (coelenteron or gastrovascular cavity)diploblastic with mesoglea polyp and medusa body formsnematocysts (specialized stinging capsules)nerve net lack excretory, circulatory & respiratory systems complex life cyclemany colonial forms exhibiting polymorphism

The largest type of jellyfish can be up to 120 feet long. (Lion’s Mane Jellyfish)In Countries like Japan, China and Korea it is a considered a delicacy to eat Jellyfish.

Did You Know?

Life Cycles

Most jellyfish have at least two distinctly different body forms in their life cycles.Polyp-This is when they take the form of a stalk with feeding tentacles.Medusa-tiny jellyfish which then grow into a large jellyfish.

Anatomy

Who preys on Jellyfish?

Jellyfish are preyed upon by; tuna, shark, pacific

salmon and sea turtles. Some

jellyfish are even preyed upon by larger jellyfish.

How do Jellyfish protect themselves?

Jellyfish use their tentacles to protect themselves, barb

like filaments found on the tentacles pierce their victim,

once this occurs venom is released from the filaments

into the victim.

How do Jellyfish move?

Jellyfish move like an umbrella, their jelly

like “skin” opens allowing water to

enter, it then closes using the pressure created from the

release of water to move.

Jelly Cam

ReferencesFisheries and Oceans Canada. (2010). Canadian Waters. Referred from:www.dfo-mpo.gc.ca/canwaters-eauxcan/bbb-lgb/library-bibliotheque/glossary-glossaire/index_e.asp

Krupp, D. (2004). Cnidarians. Referred from: http://krupp.wcc.hawaii.edu/BIOL200/powerpnt/pdffiles/cnidarchar.pdf

New World Encyclopedia. (2010). Plankton. Referred from:www.newworldencyclopedia.org/entry/Plankton

Pattern Media. (2009). Facts about Jellyfish. Reffered from:http://www.jellyfishfacts.net/facts-about-jellyfish.html

Pattern Media. (2009). Jelly Fish Facts. Reffered from:http://www.jellyfishfacts.net/jellyfish-information.html

Pattern Media. (2009). Turritopsis Nutricula. Referred from:http://www.jellyfishfacts.net/turritopsis-nutricula-immortal-jellyfish.html

Wiktionary. (2010). Jellyfish. Referred from:en.wiktionary.org/wiki/jellyfish