Echinoderms Sea star (starfish) brittle stars sea cucumbers sea urchins sand dollars * Echinoderm means _______________. Most echinoderms have spiny skin. spiny skin

Echinoderms five There are ______ characteristics of echinoderms. Most echinoderms have: Spiny skin Endoskeleton A five part body “pentaradial” A water vascular system Tube feet

bony plates called ossicles. * The internal skeleton of an echinoderm is made of bony plates called ossicles. * An echinoderm’s water vascular system is a system of tubes that carry water food and oxygen and remove wastes And helps them move

Sea Urchins spines poisonous * Sea urchins have longer and sharper ____________ that they use to protect themselves. poisonous * Some sea urchins have ______________ spines.

Sea Urchins sea plants tube feet * Sea urchins have a mouth hidden under its body. sea plants * A sea urchin uses its five teeth to eat ____________. * A sea urchin is not very active. Sometimes, it does move slowly using its __________. When not moving it uses its feet to stick to the ocean floor. tube feet

Sea Cucumber tentacles * Sea cucumbers have a mouth on their leading end. tentacles * Their mouth is surrounded by ______________ that grab up sand and organic matter. Sea Cucumbers fight with guts.

sea stars 5 Sea Stars (Starfish) Kingdom – Animalia Phylum – Echinodermata Class - Asteroidea sea stars * Starfish are also called _________________________. 5 Most Starfish have __________ arms (rays) connected to a central body.

Sea Star (Starfish) tube feet * On the bottom of the arms are hundreds of _____________ that look like suction cups. tube feet

Oral (mouth) and Aboral Bottom side top side Sea Stars have 2 sides Oral (mouth) and Aboral Bottom side top side http://wwwbio200.nsm.buffalo.edu/labs/tutor/Starfish/Starfish02D.html

Oral side- Mouth- where food enters Ambulacral (alley) groove - where tube feet are located http://wwwbio200.nsm.buffalo.edu/labs/tutor/Starfish/Starfish02D.html

Oral side- Mouth- where food enters Ambulacral (alley) groove - where tube feet are located Tube feet- used for movement and capturing prey Spines- made of calcium carbonate for protection http://wwwbio200.nsm.buffalo.edu/labs/tutor/Starfish/Starfish02D.html

Tube feet Their function is ? Review Locomotion, suction cups can grab food, pry open clam shells, Also surface can exchange gases and nitrogen waste

Aboral side- 5 arms or rays- extensions off of central disc of sea star Madreporite- looks like a wart, allows water into the water vascular system http://wwwbio200.nsm.buffalo.edu/labs/tutor/Starfish/Starfish02D.html

Aboral side- 5 arms or rays- extensions off of central disc of sea star Madreporite- looks like a wart, allows water into the water vascular system Spines- made of calcium carbonate for protection Disc- central portion of sea star http://wwwbio200.nsm.buffalo.edu/labs/tutor/Starfish/Starfish02D.html

Sunflower Starfish •Diet: crabs, sea cucumbers, snails, sea urchins, and other sea stars •Size: Largest starfish 39 inches (1 m) and has up to 24 Arms •Range: Ocean waters from Alaska to San Diego •Relatives: other sea stars, brittle stars, urchins, sand dollars, sea cucumbers;

Sunflower Starfish - feeding

This seastar is showing you its ___________ surface. Review This opening on the oral surface is the _____________ mouth This seastar is showing you its ___________ surface. aboral

* A starfish is able to re-grow its arms. This is called Regeneration

…unless they contract sea star wasting syndrome!

Scientists now link starfish die-off to warming ocean The wasting syndrome was linked to a virus and resulted in rapid disease spread, high death rates, and wasting that continued in survivors in 2015. A warming ocean is a double whammy. Warmer than usual water can stress animals, and also make infectious agents more virulent. With so much heat added by human-caused climate warming, and sea surface temperatures on the rise nearly everywhere globally, more diseases will flourish.

Review spines A Tube feet B C ambulacral groove

Underneath the Madreporite is a tube like structure called Stone Canal- funnels water into the ring canal. Water Vascular System- closed water canals provide water pressure to move tube feet

The Stone Canal is connected to the Madreporite above and the Ring Canal- circular tube which branches into 5 tubes Ring Canal delivers water to the Radial Canal then to the Ampulla and finally to Tube Feet for movement

Radial Canal is inside the ambulacral ridge (plates) Along side the ambulacral plates are the ampulla

Ampulla – are the tops of the tube feet, they act like muscular water balloons that push and pull the water in and out of the tube feet

Digestive System 2 STOMACHS: CARDIAC STOMACH PYLORIC STOMACH

CARDIAC STOMACH: Connects to mouth can be extruded out through mouth to eat objects bigger than mouth.

CARDIAC STOMACH: Connects to mouth can be extruded out through mouth to eat objects bigger than mouth. When prey is captured the jelly-like stomach actually oozes out of the tiny mouth in a process known as eversion or evisceration. Everted stomach is turned inside out, exposing the digestive enzymes to prey. The liquefied food is then absorbed through the stomach lining and into the body

CARDIAC STOMACH everting or eviscerating

PYLORIC STOMACH: located between cardiac stomach and anus Connects to the digestive glands Have no intestines only digestive glands

Digestive Glands aka PYLORIC CECA: Attaches to stomach the gland breaks down food and absorbs it 2 sets in each arm

Sea stars are carnivores: Eat molluscs and other slow moving animals

Reproductive System Underneath the digestive glands (pyloric ceca) and close to pyloric stomach is the Gonads- males produce sperm; females eggs

Fertilization is External – sperm and egg unite outside of body in the water. Fertilized egg becomes a larvae (indirect development)

Sea Stars can reproduce both sexually (sperm and egg) Asexually (Regeneration) as long as part of the central disc is there. They can also lose an arm in self-defense, in a process called autotomy.

SKELETAL SYSTEM: INVERTEBRATES (NO backbone) ENDOSKELETON made of OSSICLES (web of calcium carbonate plates) Ossicles connect to surface SPINES AMBULACRAL RIDGE contains the RADIAL NERVE and RADIAL CANAL (Ambulacral canal)

(Open) Circulatory System No heart or blood vessels; Fluid (HEMOLYMPH) in COELOM bathes organs and distributes nutrients and oxygen

Nervous System: No head/no brain (NO CEPHALIZATION) NERVE RING encircles mouth and connects to RADIAL NERVES running inside the AMBULACRAL RIDGE in each arm to coordinate movements of tube feet Body can also sense temperature, chemicals, touch EYESPOT (called an ocelli)on tip of each arm senses light/dark

INTEGUMENTARY - ”Spiny skin” SKIN GILLS = hollow tubes on aboral surface exchange gases with water and excrete nitrogen waste; SPINES for protection connect to OSSICLES below PEDICELLARIA (=pinchers) keep surface free of organisms; in some species these are venomous

Sunflower star attempting to feed on red sea urchins and scallops http://www.arkive.org/sunflower-star/pycnopodia-helianthoides/video-00.html

So, How do you Tell them APART??? structural differences The Madreporite ALL echinoderms have a madreporite In asteroids madreporite is located on top or aboral surface In brittle stars located on bottom

Starfish have a deep Groove on the oral surface of their arms Brittle stars have no grooves but instead have flat plates

The arms and disk of a starfish tend to blend in with one another. Versus a Brittle Star where the center disk is more distinct from the arms

Living Sand Dollar!

Brittle Star Sea Lily Crown of Thorns

Scotoplanes or “Sea Pigs”