Echinodermata Project

Fun Facts!

Echinodermata (no common name)

1.Sea Stars have 2 stomachs

2.Can regenerate lost limbs and even grow whole bodies from lost limbs

3.Can not live in fresh water or on  land

4.Brittle stars can be found at depths as great as 6000m

5.If a sea cucumber were placed in  fresh water it would swell up and  explode

The phylum, Echinodermata, consists of slow-moving marine animals such as starfish and sea

cucumbers. They can live anywhere from tide pools to coral reefs to deep sea trenches. Some can even regenerate limbs and part of the digestive system.

Anatomy of Echinoderms

Echinodermata

Brianna Tomlinson

Alice Yuan

Kalin Sandow

Felisa Merto

Period 2

Classes of Echinodermata

All echinoderms have an internal skeleton made up of many tiny interlocking calcium-based plates called ossicles. These ossicles are embedded within the skin. The plates are joined together by a unique catch connective tissues with adjustable stiffness. They have a water vascular system, which is a series of water-filled radial canals that extend along each arm from the ring canal surrounding the central disk. A sea star has a complete digestive system made up of a mouth, stomach, a small length of intestines, and an anus. Echinoderms can regenerate, or regrow, their limbs.

Crinoidea: filter feeders that remain attached to a surface such as the ocean floor.

Asteroidea: star shaped bottom dwellers that may be suspension feeders, opportunistic feeders, or carnivorous predators.

Ophiuroidea: most have 5 long spindly arms that they use to help move/feed; tube feet lack suckers.

Echinoidea: have a 5-part body plan but no arms,body covered with projections or spines. Most graze on food on the ocean floor.

Holothuroidea: fleshly animals with long, cylindrical shape. Tentacles are used to capture food and to feed on sediment from the ocean floor.

Common Characteristics:

Examples

Some common characteristics are their radial symmetry, several arms, digestive systems, water vascular systems, and their internal skeletons.

Sources

Reproduction:

Ophiuroidea: brittle stars & basket stars

-Brittle Stars:

• spindly arm (fast movers)
• scavengers that feed on detritus on the ocean floor.
• others are predators.

-Basket Stars:

• many branches
• filter feed by capturing plankton with their arms.

Echinoidea: sea biscuits & sea urchins

-Sea Biscuits:

• covered with tiny projections (use for movement/burrowing on the ocean floor)

-Sea Urchins:

• covered with long, sharp spines
• graze on algae by trapping it on sticky tentacles found on their ventral side.
• burrowing animals feed on wasted on the ocean floor.

Evolutionary Origins:

Echinoderms release sperm and eggs from their reproductive glands on their arms into the water. When those gametes fuse, they become a free-floating larva that matures in the water.

• Started in the cretaceous
• evolved from deutosoma
• closest relatives are the chordata

1.Nowicki, Stephen. Biology. Illinois: McDougal Littel, 2008. Print.2.Mulcrone, R. 2005. “Echinodermata” (on-line), Animal Diversity Web. May 20th, 2013 athttp://animaldiversity.ummz.umich.edu/accounts/Echinodermata/3.Zubi, Teresa. Starfish.ch. 2/27/2013. Web. 5/20/2013.www.starfish.ch/reef/echinoderms.html4.Oceanic Research Group.6/5/07.Web. 5/20/2013.www.oceanicresearch.org/eduaction/wonders/ecinoderm.html

Examples

Crinoidea: feather stars & Sea Lilies

-filter feeders use tube-like feet to collect & transfer food to their mouth.

-feather stars: moves with its arms, but is usually attached to a surface.

-sea lilies: are sessile, attached to the bottom of the ocean by a stalk on one side of their bodies.

Asteroidea: sea stars

-some are filter feeders or carnivorous predators.

-others are opportunistic feeders: will eat whatever food source.

Examples

Holothuroidea: sea cucumbers

-Sea Cucumbers:

• fleshy & have a long bilateral shape.
• tentacles: to capture particles of food (pulls tentacles through its mouth)
• sediment feeders
• absorb food items in their digestive tract
• eject non-food particles through its anus