laboratorio: parte 2 filo cnidaria - general...

LABORATORIO:Parte2

FiloCnidariaEJERCICIO8121‐138‐120(EDITION14TH)

119‐133(EDITION15TH)

Goalsfortoday

•  LearntorecognizedthePhylumCnidariafromotheranimals

•  Learnthemain‘diagnosLc’characterisLcs

•  Learnaboutsomecnidariansbiology

•  Learnabouttheinternalanatomyofanemones

Cnidaria

RadiateAnimals

•  TruemulLcellularanimals•  Radialorbiradialsymmetry

•  Simplestanimalshavinga?ssuelevelorganiza?on.

•  However,LssuesofradiatesarenotorganizedintoorganshavingspecializedfuncLons.

Porifera

Parazoa

Deu

terostom

ia

Ecdysozoa

Loph

otrochozoa

Eumetazoa

BilateriaRadiata

Protostomia

Cnidariaand

Cteno

phora

Cnidaria

Maincharacteris?csofcnidariansare:

•  DiploblasLc:twogermlayers(ectodermandendoderm).

•  InternalspacefordigesLon=gastrovascularcavity.

•  Mesoglea:isathinnoncellularlayer

•  Somehaveaskeleton(corals)butmostradiates,havefluidintheirgastrovascularcavity,andservesthemashydrosta?cskeleton.

Cnidaria


•  Cnidarianshavecnidocytes

•  CnidocytescontainsLngingorganellescallednematocysts

•  EachnematocystscontainsaLnycapsulewithacoiledthreadlikefilamentthatinjectsaparalyzingtoxin

Seevideoofnematocistsorryisinfrench!Butexcellentvisualiza?onofthisworks

Cnidaria


•  Polymorphism‐somespeciesofcnidarianshavemorethanonemorphologicalkindofindividual•  Polyp(hydroid)=sessile•  Medusa(jellyfish)=free‐living

Polyps=mayreproducebybuddingtoformclonesorcoloniesMedusas=reproducedsexually

Cnidaria:Classifica?on

Hydrozoa:

•  Bothpolypandmedusastagespresent

•  Medusawithavelum•  Freshandmarinewater

•  Examples:Hydra,Obelia,Physalia

Classes:

Scyphozoa:

•  Medusastageemphasized

•  Medusawithoutvelum•  Polypreducedorabsent

•  Enlargedmesoglea

•  Solitary

•  Examples:Aurelia

Anthozoa:

•  Allpolyps

•  Nomedusa•  Gastrovascularcavityissubdividedby

mesenteries(septa).

•  Examples:Metridium,corals

Otherclassesforwhichwedon’tspecimensbutthatyoushouldknowabout:

Cl.Staurozoa

Cl.Cubozoa

Cnidaria:YourTasksExercise8A:

–  Phylum:Cnidaria– ClassHydrozoa

•  Genus:Hydra

Hydrasarefreshwatersolitarypolypforms,butareatypicalhydrozoansbecausetheydon’thavemedusastage.

Cnidaria:Hydra

1.  LookataslideofHydrabodyparts:hypostome,mouth,tentacles.Canyouseethebasaldisc?

Cnidaria:Hydra

1.  IfyouhaveacrosssecLonofHydra,trytoidenLfythefollowingstructure.

Cnidaria:Hydra

2.Hydrasreproduceasexually.Checkifyourslideofhydrahasabud

Cnidaria:Hydra

2.Somehydraspeciesreproducesexually.Somespecieshaveseparatesexes(dioecious)oranindividualmayhaveboth(monoecious).Yourinstructorhashydraswithovaries.Forcomparisonlookatthisphotoofanhydrawithtestes

testes Ovary

Cnidaria:Hydra

3.YourinstructorhasstagedaslideofanHydranematocysts

Cnidaria:SomethingyoushouldknowExercise8A:


•  Genus:Physalia

Physaliaphysalis“Theman‐ofwar”isodenmistakenforajellyfish.However,thisanimalisafloaLnghydrozoancolony,madeupoffourpolyptypes:pneumatophore(float),dactylozooids(tentaclesfordefenseandpreycapture),gastrozooids(feeding),andgonozooids(reproducLon)

Look at the preserved Physalia

Cnidaria:YourTasksExercise8A:


•  Genus:Obelia

Obeliaisamarinecolonialhydroid.Obeliahasbothpolyp(hydroid)anda?nymedusa(jellyfish).

Cnidaria:Obelia

1.  LookforyourslideofObelia.Thecolony:

Coenosarc Living part of the colony stem

Perisarc Non-living protective cover that protects the coenosarc

Cnidaria:Obelia

1.  LookforyourslideofObelia.ReproducLvepolyps

Gonangium Reproductive poly with medusae that arise by budding

Gonotheca

Gonopore

Medusa buds

Cnidaria:Obelia

1.  LookforyourslideofObelia.Feedingpolyps

Hydrotheca Hydrant Feeding polyp that captures and ingests prey

Cnidaria:Obelia

1.  LookforyourslideofObelia.Thecycle

The life cycle of Obelia alternates between a sessile polyp stage and a swimming medusa stage.

Cnidaria:Obelia

2.LookattheslideoftheLnyObeliamedusa.Medusasaredioecious

Cnidaria:YourTasksExercise8B:

–  Phylum:Cnidaria– ClassScyphozoa

•  Species:Aureliaaurita

Aureliaaurita“moonjelly”isamarinescyphomedusa.Themesogleaisthicker.Sexesareseparate.Thegastrovascularsystemhasmorecanals.Theyhaveatretamerousradialsymmetry.

Cnidaria:Aurelia

1.Takealookofscyphomedusabodyparts

A= mouth B= Gonad C= oral arm D= gastric pouch E= radial canals F= ropalium (sense organ containing statocyst and ocellus)

Cnidaria:Aurelia2.Aureliaauritalifecycle

Larvae planula

Strobila stages Ephyra

Medusa

Cnidaria:YourTasksExercise8C:

–  Phylum:Cnidaria– ClassAnthozoa

•  Species:Metridiumsenile

Metridiumsenileisacommonspeciesinnorthernseas.TheyodenreproduceasexuallybypedallaceraLon,andaresaidtobecapableofbinaryfissionaswell.SexualreproducLonalsooccurs.Dietismostlysmallzooplankton,thoughtheymayalsoeatsmallbenthicpolychaetes,fish,andsquid.anemone

Cnidaria:Metridium

1.Takealookattheexternalanatomy

A= mouth B= oral disc C= tentacles D= column E= acontia (armed with nematocysts)

F= pedal disc

Cnidaria:Metridium1.Takealookattheinternalanatomy

Cnidaria:YourTasksExercise8C:

–  Phylum:Cnidaria– ClassAnthozoa

•  Corals

Cnidaria:Corals

1.Observedthecoralexamplesinthetable.Makesuretonotedifferencesbetweenthemandthesponges!

Coralsaremarine,typicallylivingincompactcoloniesofmanyidenLcalindividual"polyps".Thegroupincludestheimportantreefbuildersthatinhabittropicaloceans,whichsecretecalciumcarbonatetoformahardskeleton.

wikipedia

Cnidaria:YourTasks

IndividualheadsgrowbyasexualreproducLonofindividualpolyps.Coralsalsobreedsexuallybyspawning.Polypsofthesamespeciesreleasegametessimultaneouslyoveraperiodofonetoseveralnightsaroundafullmoon.

Acoral"head",whichappearstobeasingleorganism,isacolonyofmyriadgeneLcallyidenLcalpolyps.Eachpolypistypicallyonlyafewmillimetersindiameter.

wikipedia

1.Observedthecoralexamplesinthetable.

Cnidaria:YourTasks

Elblanqueamientoenloscoraleso"coralbleaching"serefierealapérdidaoexpulsióndezooxantelaenlasanémonas,coralesyotrosorganismofotosintéLcos,asícomotambiénalareduccióndepigmentosenlazooxantelacuandolamismaexpulsalasproteínasquecaracterizansucolor.

Zooxantela

BlanqueamientodeCorales

Althoughcoralscancatchsmallfishandanimals,suchasplankton,usingsLngingcellsontheirtentacles,mostcoralsobtainthemajorityoftheirenergyandnutrientsfromphotosyntheLcunicellularalgaecalledzooxanthellae.

What are the consequences of bleaching for the reef?

ImportantLinksCnidaria

http://www.ucmp.berkeley.edu/cnidaria/cnidaria.html

http://biodidac.bio.uottawa.ca/Thumbnails/searchresults.htm?frompage=1&StartRow=513&sujet=&formattype=&auteur=Houseman&keyword=&phylum=&datesoumis=&maxrows=64

http://www.biology.ualberta.ca/courses.hp/zool250/Labs/Image-key.htm

http://www.biol.wwu.edu/donovan/biol460/Biology_460.html

laboratorio: parte 2 filo cnidaria - general...

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