1 / 11

PHYLUM ECHINODERMATA (spiny skin)

PHYLUM ECHINODERMATA (spiny skin). Sea star Sea urchin Sand dollar Sea cucumber. ECHINODERM CHARACTERISTICS. Calcareous endoskeleton ossicles Biscuit sea star Tosia australis Adults with pentaradial symmetry (No cephalization oral / aboral) Water-vascular system

marvin
Download Presentation

PHYLUM ECHINODERMATA (spiny skin)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. PHYLUM ECHINODERMATA(spiny skin) Sea star Sea urchin Sand dollar Sea cucumber

  2. ECHINODERM CHARACTERISTICS • Calcareous endoskeleton • ossicles • Biscuit sea starTosia australis • Adults with pentaradial symmetry • (No cephalization oral / aboral) • Water-vascular system • Complete digestive tract • Nervous system consisting of nerve net, nerve ring, radial nerves

  3. characteristics • Tube feet • deuterostomes • coelomates whose embryos have radial cleavage

  4. classes • 7 000 species • 80 species are sessile (non-motile) • 6 existing classes

  5. Class Holothuroidea • Sea cucumbers • 1 500 species • Sluggish burrowers / creepers • No rays • Elongate • Permanent ventral • Bilateral symmetry

  6. Class Holothuroidea • Muscular system • Swim by undualting • Body wall muscles contract in worm like waves • Respiratory system • Respiratory trees • Water force circulated by rectum contractions

  7. Class Holothuroidea • Nervous system • Additional nerves to tenatacles • Statocysts • maintain orientation • Photoreceptors • light detectors

  8. Class Holothuroidea • Circumoral tentacles • tube feet surround mouth • Digestive system • stomach • Long, looped intestines • Rectum • anus • Snot sea cucumberLeptosynapta dolabrifera

  9. Class Holothuroidea • Eviseration for defense • Tranverse fission • regeneration • Dioecious single gonad • External fertilization • trepang

  10. predator • About the only thing that eats orange sea cucumbers are sea stars. It took an 18 cm sunflower star 22 hours to eat an 8 cm sea cucumber.   Other sea star predators include the orange sun star and the leather star. 

  11. Eleven arm sea star Coscinasterias muricata

More Related