phylum echinodermata notes - sardis secondary echinodermata...general characteristics hard, spiny,...

Download Phylum Echinodermata Notes - Sardis Secondary   Echinodermata...General characteristics Hard, spiny, or bumpy endoskeleton covered with a thin ... Phylum Echinodermata Includes

Post on 23-Mar-2018

224 views

Category:

Documents

6 download

Embed Size (px)

TRANSCRIPT

  • PhylumEchinodermataBiology11

  • Spiny Radialsymmetry Watervascularsystem Endoskeleton

    Generalcharacteristics

  • Hard,spiny,orbumpyendoskeletoncoveredwithathinepidermis.

    Endoskeletoncomposedofcalciumcarbonate(limestone).

    Somespinesaremodifiedintopedicellariae forprotectionorselfcleaning.

    Canbeeitherrigid(aswhenwetrytopulloneoffofarock)orveryflexible(whenrightingitself),sinceendoskeletonismadeofplatesjoinedbymuscleswhichcancontractorrelax.

    Endoskeleton

  • Enablessessile&slowmovinganimalstosensepotentialfood,predators,andotheraspectsoftheirenvironmentfromalldirections

    RadialSymmetry

  • 1.ClassAsteroidea: Ex.Seastars Mostspecieshave5ormorearms

    2.ClassOphiuroidea: Ex.BrittleStar&basketstar Compactsize;movequickly Armsusedformotility

    EchinodermDiversity

  • 3.ClassCrinoidea: Ex.Sealilies&featherstar Fewlivingspeciesremain Sealiliesareattachedtotheoceanfloor Featherstarsbeginattachedbutbreak

    awayandswimfreely

    4.ClassEchinoidea: Ex.Seaurchin&sanddollar Bodiesshapedlikespheresordisks;no

    arms Solid,internalshell Specialfeedingstructurescalled

    Aristotleslantern:madeupoffivesharp,triangulartoothlikesstructuressurroundingthemouth

    EchinodermDiversity

  • 5.ClassHolothuroidea: Ex.Seacucumber Noarms;elongatedbody Bilaterallysegmented Lieandmoveononesideonly

    EchinodermDiversity

  • SeaStars(ClassAsteroidea)

  • Radialsymmetry Haveadorsalandventralside,butnoanteriorandposteriorends

    Fivepartbodyplan NOcephalization(i.e.nobrain)

    SeaStarGeneralCharacteristics

  • MovementcarriedoutbyWATERVASCULARSYSTEM WVS:Anetworkoffluidfilledtubesthatenabletheseastarto

    move Alongtheundersideofeachoftheseastarsarmsaremany

    pairsofTUBEFEET Tubefeet:externalstructuresofthewatervascularsystem

    OntopofeachtubefootisanAMPULLA Ampulla:muscularsacthathelpsforcewaterthroughtheWVS

    Musclesoftheampullaecontract,pushingwaterintothetubefootcausingittoextend

    Whenthefootattachestoasurface,itcontracts,pushingthewaterbackintotheampullaeandpullingtheseastarforward

    SeaStarMovementandSupport

  • Systemenablesthemtomove,exchangegases,capturefood,andexcretewastes

    Waterentersthemadreporite ringcanallongradialcanals hollowtubefoot

    SeaStarWaterVascularSystem(WVS)

  • Allechinodermshaveamouth,stomachandintestines.

    Seastarsarecarnivorous Feedonmollusksbyextrudingtheir

    stomachthroughtheirmouthontothefood.

    Tubefeetaidinpryingapartshellsofmollusks.

    Powerfulenzymesaresecretedbyapairofdigestiveglandsineacharm

    Thestomachthenabsorbstheliquidfood.(Nointestineneeded).

    SeaStarDigestion

  • Thereisaheartlikesacunderthemadreporite thatpushesfluidnearlyidenticaltoseawaterthroughthecoelem,bathingallorgans

    Thefluidiskeptinmotionbybeatingcilia.

    Skingillsandtubefeetbringinoxygentothisfluid.

    SeaStarCirculationofNutrients

  • Wastesareflushedfrombodythroughthetubefeetorskingills.

    Aseastaralsohasananus,locatedinthecenterofthedorsalside.

    SeaStarExcretion

  • Nobrainorevenfusedganglia,onlyacentralnerveringthatsurroundsthemouth

    Nervesextendfromthenerveringdowneachray(belowradialcanals)intoanervenetthatissensoryandcoordinatesmovement

    Nosensoryorgans,onlycellsthatdetectlight&touch Haveeyespotsattheendofeacharmthatallowthemtodetectlight,andchemicalreceptorsontheirtubefeet

    SeaStarNervousSystem

  • Seastarsareseparatelysexed. Twoovariesortesteslieinthecornersofeacharmandopendirectlytotheexterior

    Spawningbyonecanresultinthosenearbytoalsospawn

    SeaStarReproduction

  • SeaStars

    PhylumEchinodermataIncludes

  • BrittleStars Fragile:rayswill

    breakoffwhenpickedup.

    PhylumEchinodermataIncludes

  • SeaUrchinsandSandDollars

    Coveredinspines. Norays

    PhylumEchinodermataIncludes

  • SeaCucumbers Leatherycovering

    allowsflexibility. Whenthreatened,

    mayexpeltubesfromanusorreleaseinternalorganstoconfusepredator.

    PhylumEchinodermataIncludes

  • SealiliesandFeatherstars

    Featheryarmsallowittoswim.

    PhylumEchinodermataIncludes

  • Seadaisies Tubefeetlocated

    aroundedgeofdisk. Lessthan1cmin

    diameter Discoveredin1986

    PhylumEchinodermataIncludes