Nyob rau hauv cov tsiaj invertebrate peb pom ntug ntawm cnidarians, ib pab pawg neeg nthuav uas muaj ib tug tseem ceeb ntau haiv neeg. Lub npe cnidarian yog muab los ntawm lo lus "cnidocytes", tshwj xeeb hlwb tshwj xeeb rau cov pab pawg. Qee cov tswv cuab ntawm cov phylum no yog cov tsiaj tuag rau tib neeg, thaum lwm tus tuaj yeem ua rau muaj kev cuam tshuam me me thiab qee qhov yuav luag tsis pom.
Koj puas xav paub cnidarians? Peb caw koj los nyeem cov lus no hauv peb lub vev xaib kom kawm txog hom cnidarians, cov piv txwv tshwj xeeb, lawv cov yam ntxwv tseem ceeb thiab ntau ntxiv.
Cnidarians yog dab tsi?
Cnidarians are invertebrate animal of aquatic life and with a complex Constitution than sponges, but me dua ob tog. Txawm hais tias qhov kawg no, lawv tuaj yeem ua tau zoo ntawm cov tsiaj nyeg ntau dua li lawv tus kheej.
Lawv muaj cov ntaub ntawv keeb kwm yav dhau los, uas hnub rov qab txog 700 lab xyoo. Yog li ntawd, nyob rau hauv lub cnidarians peb pom ib tug tseem ceeb ntau haiv neeg, sawv cev los ntawm ntau yam zoo nkauj thiab coj txawv txawv cov ntaub ntawv, uas muaj xws li cov nroj tsuag-zoo li tus hydroids, paj zoo li anemones, jellyfish thiab peculiar horny corals thiab pob zeb corals, uas tsim lub fascinating coral reefs, uas yog txuam nrog ib tug biodiversity ntawm zoo ecological tseem ceeb.
Type of Cnidarians
Kev faib tawm ntawm cnidarians, raws li Integrated Taxonomic Classification System [1], sib raug raws li hauv qab no:
- Nyob Kingdom
- Phylum: Cnidaria
Thiab, peb paub qhov txawv peb subphyla, nyob rau hauv uas txawv hom cnidarians yog pab pawg. Thawj ntawm cov no yog anthozoa Ntawm no yog chav kawm Anthozoa suav nrog, uas pab pawg corals, paj tsiaj thiab hiav txwv anemones
The second subphylum is Medusozoa, which group the medusas thiab muab faib ua cov chav kawm hauv qab no:
- Cubozoa (sea wasps, box jellyfish)
- Hydrozoa (Hydrozoa)
- Polypodiozoa (polypodiozoa)
- Scyphozoa (kab pheeb suab)
- Staurozoa (stauromedusae)
Thaum kawg, peb muaj lub subphylum Myxozoa, uas pab pawg myxozoa (uas yog microscopic parasites) thiab muab faib ua ob chav:
- Malacosporea
- Myxosporea
Raws li tus naj npawb ntawm cov tsiaj hauv cnidarians, kwv yees li ntawm 10,000 kwv yees.
Cnidarian tsiaj
Tam sim no peb paub ntau hom cnidarians, peb tuaj yeem kwv yees tias nws nyuaj los tsim cov yam ntxwv zoo ib yam rau txhua tus. Txawm li cas los xij, feem ntau, peb yuav hais txog cov yam ntxwv tseem ceeb ntawm cov tsiaj cnidarian:
- Tag nrho cov tswv cuab ntawm cov phylum yog cov tsiaj txhu tshwj xeeb.
- Lawv muaj radial symmetry.
- Lawv tsis muaj lub taub hau, yog li qhov kawg ntawm lub cev hu ua qhov ncauj, ze lub qhov ncauj, thiab aboral (tawm ntawm lub qhov ncauj).
- Cnidarians muaj ob hom qauv: polyps lossis jellyfish. Qee hom muaj ob qho tib si, nyob ntawm theem uas lawv pom, xws li qee qhov hydrozoans thiab chav Scyphozoa.
- Hauv qee hom, xws li corals thiab anemones, polyp cov ntaub ntawv feem ntau muaj lub cev tubular, nrog tentacles nyob ib ncig ntawm lub qhov ncauj, thiab feem ntau yog tsau rau lub substrate ntawm lub aboral kawg, qhov twg muaj ib tug qauv. uas yog qee zaum disc-puab. Hom cnidarian no tuaj yeem nyob ib leeg lossis hauv ib lub koom haum hu ua colony.
- Jellyfish zoo li cnidarians feem ntau muaj lub tswb- lossis lub kaus zoo li lub cev, nrog lub cev sib npaug. Feem ntau, nyob rau hauv cov ntaub ntawv no lub qhov ncauj nyob rau hauv qhov chaw, nyob rau sab concave ntawm tus tsiaj, nrog rau tentacles nyob ib ncig ntawm lub kaus.
- Tag nrho cov tswv cuab ntawm cov phylum no muaj cov kab mob endoskeleton los yog exoskeleton, uas tej zaum yuav yog chitinous, calcareous los yog protein nyob rau hauv muaj pes tsawg leeg.
- Ib txhia muaj tshuaj hu ua mesoglea, uas ua haujlwm raws li hydroskeleton thiab, txawm hais tias nws muaj dej ntau, nws kuj yog tsim los ntawm proteins, collagen thiab lwm yam khoom. Cov tshuaj no pom, piv txwv li, hauv coral thiab jellyfish.
- Lub cev ntawm cnidarians muaj ib qho qhib, uas ua haujlwm raws li ob lub qhov ncauj thiab qhov quav. Qhov no hu ua gastrovascular kab noj hniav.
- Cov tsiaj no feem ntau muaj tentacles nyob ib ncig ntawm lawv lub qhov ncauj.
- Raws li ib tug tshwj xeeb feature ntawm lub phylum, cnidarians muaj ib co cov hlwb tshwj xeeb hu ua cnidocytes, ntau heev nyob rau hauv lub tentacles, uas lawv txhaj. tshuaj chemicals uas immobilize lawv prey; lawv kuj siv lawv los tiv thaiv. Qee hom muaj cov tshuaj tua kab mob rau tib neeg, ib yam li qee hom ntawm Cubozoa.
- Cnidarians kuj muaj lwm cov hlwb tshwj xeeb, suav nrog cov leeg nqaij thiab cov hlwb. Cov tom kawg muaj peev xwm ntawm synapsing.
- Lwm tus yam ntxwv ntawm cnidarians yog lawv tsis tau txhais lub cev.
- polyp-shaped cnidarians yog sessile, thaum jellyfish-zoo li tus tuaj yeem nqa mus los ntawm cov dej ntws. Txawm li cas los xij, tsis ntev los no tau muaj pov thawj tias lawv muaj peev xwm ua luam dej, uas lawv vam khom kev txav ntawm lub cev.
- Lawv muaj lub paj hlwb uas tswj cov txheej txheem tseem ceeb.
- Lawv muaj cov qauv kev xav, uas tso cai rau lawv teb rau cov stimuli xws li lub teeb, kub lossis siab hloov, thiab lwm yam.
- Cov khoom noj uas tsis tau noj tau raug tso tawm hauv qhov ncauj.
- Ua pa tawm los ntawm lub cev lub hlwb, uas coj cov pa oxygen thiab tso carbon dioxide.
Cnidarian chaw nyob
Cnidarians, raws li peb tau hais, tsuas yog cov tsiaj nyob rau hauv dej, zoo yoog nyob rau hauv ib puag ncig no. Feem coob ntawm cov tsiaj nyob nyob rau hauv dej ntsev ecosystems, txawm li cas los xij, qee hom tsiaj nyob hauv dej tshiab.
Nyob ntawm hom, cnidarians tuaj yeem ua neeg nyob lossis txwv rau qee qhov chaw nyob. Ntawm qhov tod tes, nyob ntawm tus tsiaj lawv kuj tsim hauv dej tob lossis ntiav, nrog rau qhov kub thiab txias sib txawv. Tsis tas li ntawd, qee qhov nyob hauv cov dej qhib, thaum lwm tus mus rau ntug hiav txwv. Cnidarians uas ua luam dej txav ntawm ib qho chaw mus rau lwm qhov nyob ntawm qhov xwm txheej ntawm ib puag ncig.
Piv txwv ntawm cnidarian habitats
Piv txwv li, peb pom cov moon jellyfish (Aurelia aurita), uas muaj ib tug dej faib thoob plaws hauv dej hiav txwv, tshwj tsis yog hauv Arctic, yog li nws nyob hauv hiav txwv ntawm Asmeskas, Asia, Europe, Australia thiab qee thaj chaw ntawm Africa. Cov dej qab zib jellyfish (Craspedacusta sowerby), ntawm qhov tod tes, yog ib txwm nyob rau hauv cov dej qab zib hauv Asia, zoo li cov tswv cuab ntawm genus Hydra, uas nyob hauv dej tshiab. Thiab rau nws ib feem, qhov txaus ntshai hiav txwv wasp (Chironex fleckeri) feem ntau txwv rau Australian maritime waters thiab rau Southeast Asia.
Ntawm qhov tod tes, lub coral reefs, uas tuaj yeem tsim los ntawm ntau hom cnidarians, muaj ntau qhov chaw nyob, cov uas feem ntau yog txuam nrog tropical-type seas, ntawm qhov tob uas feem ntau tsis tshaj 50 meters, nrog rau qhov kub ntawm 20 mus txog 28 ºC thiab tej yam kev mob ntawm ntsev. Cov no yog ib feem ntawm cov khoom siv hauv hiav txwv zoo heev nrog rau kev cuam tshuam rau lub ntiaj teb, thiab tseem cuam tshuam nrog lwm cov ntug dej hiav txwv ecosystems, uas lawv muab kev sib nrig sib pab.
Cnidarian noj
Vajtswv hom cnidarian, muaj hom pub rau cov tsiaj no. Yog li, qee qhov yog cov tsiaj nyeg, xws li jellyfish, uas tua lawv cov tsiaj uas siv lawv cov tentacles, lub qhov ncauj caj npab thiab cov tshuaj lom cnidocytes ua rau tuag tes tuag taw thiab tom qab ntawd noj lawv. Ntawm qhov tod tes, sessile lub neej cnidarians, xws li corals, pub los ntawm filtering yaj nyob rau hauv dej, absorbing hais. Qee hom tau txais cov as-ham los ntawm algae uas lawv tsim kev sib raug zoo symbiotic, uas nyob hauv cov tsiaj, uas yog vim li cas lawv hu ua endosymbionts.
Yog li, nyob ntawm hom, cnidarians pub rau:
- Zooplankton
- Fishes
- Mollusks
Cnidarian reproduction
Cnidarians tuaj yeem muaj hom , nrog rau qhov tshwj xeeb uas ntau hom muaj ob hom kev loj hlob. Nyob rau hauv asexual reproduction, buds yuav sprout los ntawm outgrowths ntawm lub cev uas tom qab los. Hauv lwm qhov xwm txheej, cov tib neeg tuaj yeem faib ua ib nrab thiab txawm tias qee cov chav kawm Anthozoa rov tsim dua los ntawm kev faib tawm saum lub cev. Nyob rau hauv tsab xov xwm ntawm Asexual Reproduction nyob rau hauv Tsiaj txhu peb tham nyob rau hauv kom meej ntxiv.
Raws li kev sib deev kev sib deev, nws muaj feem xyuam rau cov tsiaj uas muaj lub neej theem nyob rau hauv daim ntawv ntawm ib tug polyp (uas faib asexually) thiab lwm yam raws li ib tug jellyfish, uas sib haum mus rau kev sib deev nws tus kheej. Nyob rau hauv txoj kev no, muaj cov dioecious cnidarians, uas yog, qee tus txiv neej thiab lwm tus poj niam, uas tsim cov phev thiab ovules, feem. Yog tias koj txaus siab xav nkag mus tob rau hauv lub ncauj lus no, tsis txhob nco cov ntawv tshaj tawm no ntawm Jellyfish Reproduction.
Piv txwv ntawm cnidarian tsiaj
Peb twb tau hais lawm tias cov tsiaj txhu cnidarian yog ib pawg neeg sib txawv, tab sis cia peb ua raws qee yam piv txwv ntawm hom:
Class Anthozoa
Hauv chav kawm no peb pom cov tsiaj uas muaj paj zoo li cov paj ntoo, nws kuj suav nrog ntau yam hom corals, Anemones, Feathers and Seafans. Qee qhov piv txwv yog:
- Staghorn Coral (Acropora cervicornis)
- Pale anemone (Aiptasia pallida)
- Caribbean Giant Anemone (Condylactis gigantea)
- Slotted Brain Coral (Diploria labyrinthiformis)
- Common Sea Ntxuam (Gorgonia ventalina)
Class Cubozoa
Ntawm no peb tau nquag hu ua " box jellies" vim yog lub square zoo li tus ntoo khaub lig seem ntawm lub tswb. Lawv yog cov active predators thiab zoo swimmers. Qee qhov piv txwv yog:
- Irukandji Jellyfish (Carukia barnesi)
- Sea Wasp (Chironex fleckeri)
- Hikurage or Fire Jellyfish (Virulent Morbakka)
- Mangkaprun Klong or sarong (Chironex indrasaksajiae)
Class Hydrozoa
Nws yog ib pawg neeg sib txawv heev, nrog rau ob qho polyp thiab medusa theem, nrog rau cov txheej txheem kev xeeb tub. Ntawm nws cov tswv cuab peb pom:
- Portuguese warship (Physalia physalis)
- Freshwater polyp (Hydra viridissima)
- Paj Kaub Jellyfish (Olindias formosa)
- Genus fire coral (Milleporidae dichotoma)
- Cua Sailors (Velella velella)
Class Polypodiozoa
Nws yog ib tug genus ntawm parasitic cnidarians thiab tsuas muaj ib hom: Polypodium hydriform. Nws qhov chaw taxonomic tab tom tshuaj xyuas. Interestingly, nws nyob hauv hlwb ntawm lwm yam tsiaj:
Class Scyphozoa
Ntawm no peb pom feem ntau ntawm jellyfishCnidarians ntawm chav kawm no tau zoo sib txawv hauv cov chaw nyob, los ntawm Arctic mus rau cov dej kub kub. Lawv yog cov cnidarians ntau heev nyob rau hauv ntug dej hiav txwv, txawm hais tias ib txhia nyob ntawm tej qhov tob. Piv txwv suav nrog:
- Moon jellyfish (Aurelia aurita)
- Sea nettle (Chrysaora quinquecirrha)
- Lion's mane (Cyanea capillata)
- Golden jellyfish (Mastigias papua)
- Cannonball jelly (Stomolophus meleagris)
Class Staurozoa
Cov hauv pawg no feem ntau yog cov tsiaj me, cuam tshuam nrog cov dej boreal thiab feem ntau yog adhered rau qee qhov substrate. Nws cov tswv cuab suav nrog:
- Stemmed jellyfish (Haliclystus antarcticus)
- Spotted kaleidoscope jellyfish (Haliclystus octoradiatus)
- Stalked jellyfish (Mania handi)
- Stalked Trumpet Jellyfish (Depastromorpha africana)
- Trumpet tswb jellyfish (Lipkea stephensoni)
