Echinoderms

Developed By Adam F Sprague & Dave Werner

MATES Biology(Marine Bio Book – Ch.7)(Biology Book – Ch.40)

5 classes of Echinoderms

• Sea star or starfish ____________

• Brittle stars, basket stars, serpent stars _________________

• Sea urchins, heart urchins and sanddollars )_______________

• Holothurians or sea cucumbers ________________________

• Feather stars and sea lilies ___________________

Characteristics of Echinoderms

• _____________ symmetry

• body = ________________________, each containing _______________ set of internal organs

• no ____________________________, but some brittle stars have light sensitive parts on arms

• Mouth-situated on _____________ & anus on top (except feather stars, sea cucumbers & some urchins).

Characteristics of Echinoderms

• tentacle-like structures =________

__________________

• tube feet -__________________ controlled by vascular system- supplies ________ through canals

• Water creates _______ effect

Ecology and range of Echinoderms

• exclusively ________

• occur in various habitats from ______________ zone to bottom of deep sea trenches & from _______ to rubble to ________ and in cold and tropical seas.

Behavior of Echinoderms

• Some _______________ (i.e. sea star), _________________ foragers (i.e. sea cucumbers) or ___________________ feeders (i.e. basket stars)

• Reproduction carried out by release of ________ & ___________ into water. Most species produce pelagic (_______________) planktonic larvae which feed on plankton

Behavior of Echinoderms

• can __________________- missing limbs, arms, spines - even intestines (i.e. sea cucumbers).

• Some brittle stars & sea stars can reproduce ___________ by breaking a ray or arm or by deliberately splitting the body in half. Each half = whole new animal.

Sea stars (starfish)(Asteroidea)

Characteristics• radial symmetry, several arms (5 or multiplied by 5)

radiating from a __________________• _____________________ close together • water intake (________________)• upper surface is often very ________________. • Minute pincer-like structures called

______________________ are present. These structures ensure that the surface of the arms stay free from algae.

• _________________ is often a lighter color.

Sea stars (starfish)(Asteroidea)

• Ecology and range or sea stars

–The starfish lives _________________ in the coral reef and on sand or rocks

Sea stars (starfish)(Asteroidea)

• Behavior of sea stars – majority are ______________ -

feed on sponges, bryozoans, ascidians & molluscs

– ___________________ feeders (detritus = organically enriched film that covers rocks) or scavengers.

– Some are ______________ feeders, i.e. crown-of-thorns feeds on live coral polyps.

Sea stars (starfish)(Asteroidea)

• Behavior of sea stars

• ____________________

• (asexual reproduction =________________)

• In others the body is broken into unequal parts (= ________________) then the missing limbs regenerate

Sea urchin(________________________)

• Characteristics of sea urchins • Radial symmetrical body with external

_________________ skeleton and a centrally located jaw (called __________________________) with horny teeth

• mouth consists of a complex arrangement of ___________ and _____________ surrounding circular opening

• The ____________ is located on the upper surface. Some sea urchins have a spherical, bulb like _________- (to store fecal material) that protrudes from the anal opening. can be withdrawn into shell.

Sea urchin(Echinoidea)

»Ecology and range of sea urchins

• Rubble and sand. An abundance of sea urchins can be a sign for ____________ water conditions

Sea urchin(Echinoidea)

• Behavior of sea urchins

• Locomotion by _________________________

• generally _______________________

• Most are ________________ -some feed on sponges, bryozonans and ascidians and others on detritus (detritus = organically enriched film that covers rocks).

• The sexes are _______________ & young are formed indirectly by the fusion of sperm and eggs released into the water.

Sea CucumbersHolothurians

(_____________________________)• Characteristics of sea cucumbers

– holothurians are _________________ (distinct dorsal and ventral side)

– as name suggests, they are __________________ shaped w/ an elongated, muscular, __________________ w/ mouth at one end & anus at the other. _____________________ around mouth (modified ______________-) used in food collecting

Sea CucumbersHolothurians (Holothuroidea)

• Ecology and range of sea cucumbers

– _________________. Also seen on some sponges in large aggregations.

Sea CucumbersHolothurians (Holothuroidea)

• Behavior of sea cucumbers – Most species feed on __________________

coating sandy surfaces

– crawl over bottom ingesting sand. The edible particles (organic matter such as plankton, _________________ and bacteria) are extracted when passing through their digestive tract & processed sand is expelled from anus (as _______________ excrements).

Sea CucumbersHolothurians (Holothuroidea)

• Behavior of sea cucumbers

• move by means of _________________

• When attacked they _______ a sticky thread like structure which is actually parts of their ________. The so called ______________ threads are toxic (the poison is called holothurin) and can dissuade many potential predators. These structures quickly ________________.

Feather stars(____________________)

• Characteristics of feather stars» Characteristics of feather stars

• AKA- _____________.

• ___________ symmetry

• The body is _________________, their numerous feathery _____________ project from a central disc

• 5-200 arms, called ________________- -coated w/sticky substance to catch food.

• appendages known as ___________ attached to the underside of the body with which they cling to to sponges or corals.

• mouth and their anus on _________ side.

• Ecology and range of feather stars– primarily ____________ but seen in the open during the day with arms

rolled up.

– Crinoid stalks and blastoid heads are common __________ in certain parts of North America.

– Specimen of the Carboniferous crinoid Paradichocrinus planus

Feather stars(Crinoidea)

»Behavior of feather stars

• Feather stars can ___________________

____________________ but usually they cling to sponges or corals. Feather stars are very abundant in areas exposed to periodic strong ____________, because they feed on _____________ food.

Brittle stars(___________________________)• Characteristics of brittle stars

» Characteristics of brittle stars

– close relatives of ________________

– _______________ symmetry-five ___________________ arms

– no _______________ of internal organs, just one set in the central disk

– Compared to starfish, brittle stars have a much ____________________ and no _____

– Wastes are eliminated through the mouth on underside

Brittle stars(Ophiuroidea)

• Ecology and range of brittle stars

– very _________ & hide in crevices under corals

– Best seen at ____________ time, when they emerge to feed on plankton. Usually at places exposed to strong currents.

Brittle stars(Ophiuroidea)

• Behavior of brittle stars

– Brittle arms= an _____________ mechanism.

– _________ regenerate quickly and an entire new organism can regenerate, if the broken arm is attached to a sizeable portion of the ______

– reproduce ______________ by self-division

– Brittle stars are the most ____________ and ____________- moving echinoderms