peb feem coob tau ntsib tus tsiaj xav paub no nyob rau qee lub sijhawm thiab, tej zaum, koj twb tsis muaj hmoo txaus los raug mob hnyav los yog muaj hmoo txaus tau pom tus tsiaj zoo nkauj no nyob hauv dej hiav txwv.
Koj puas tau xav tias cov tsiaj no raug tsa li cas? Interestingly, jellyfishreproduction tsis muaj nyob rau hauv cov poj niam li nws ua nyob rau hauv cov tsiaj. Yog tias koj xav nrhiav seb nws tsim tawm li cas, tsis txhob yig, nyeem cov ntawv no ntawm peb lub xaib.
Chaw ua si ntawm jellyfish
Jellyfish belongs rau "Cnidaria" Phylum, uas encompasses ib co 10,000 hom, uas tsuas yog 20 yog cov dej tshiab, txij li qhov seem yog dej hiav txwv. Lawv muaj thawj radial symmetry (kev faib ntawm ib tug tsiaj rau hauv ib nrab zoo sib xws raws li longitudinal axis ntawm lub cev) nyob rau hauv ntau qhov thib ob hloov mus rau biradial los yog ob sab (ib leeg. dav hlau faib tsiaj ua ob halves, sab laug thiab sab xis).
Nws lub cev raug teeb tsa ua lub hnab dig muag nrog ib lub qhovrau kev nkag ntawm cov zaub mov thiab tawm ntawm cov pov tseg, nrog rau lub plab zom mov hu ua "gastrovascular kab noj hniav", gastrocele lossis coelenteron, thiab ua haujlwm los ntawm kev zom zaub mov thiab xa cov as-ham thiab oxygen mus rau lwm lub cev.
Txiv kab ntxwv lub qhov ncauj zoo li lub tswb lossis lub kaus, tsim lub kaus tus yam ntxwv ntawm cov tsiaj no. Lawv sawv tawm rau qhov muaj lub siab xav tau lub cev, nyob ntawm ntug ntawm lub kaus. Peb pom cov kabmob pom (ocelli) thiab cov kabmob zoo li qub (statocysts), uas ua haujlwm kom muaj kev sib npaug. Jellyfish tuaj yeem ua tau predatory los yog suspensivorous (lim dej nyob ib ncig ntawm lawv, yog li ntxiab cov khoom noj me me).
Lawv kuj muaj cov hlwb tshwj xeeb hu ua "cnidocytes". Muaj ob peb hom, tab sis feem ntau yog cov nematocyst, uas yog stinging, nrog rau kev yos hav zoov thiab tiv thaiv kev ua haujlwm. Lub nematocyst yog tam sim no nyob rau hauv nws tentacles thiab los ntawm nws nws provokes lub stings. Lwm yam tseem ceeb yog pticocysts, lawv tso cov hnoos qeev uas ua haujlwm rau ntes cov tsiaj me los yog cov khoom noj khoom haus.
Lwm yam yam ntxwv tseem ceeb ntawm cov tsiaj no yog lawv muaj ob lub cev: daim polyp, uas feem ntau yog benthic (nyob anchored rau seabed) thiab feem ntau colonial (nyob rau hauv loj pab pawg neeg) thiab daim ntawv medusa, planktonic (lub neej ntab hauv dej) thiab feem ntau nyob ib leeg. Muaj cov tsiaj uas tsuas muaj daim ntawv polyp xwb, lwm tus tsuas yog jellyfish thiab lwm tus uas muaj ob hom ntawv hauv lawv lifecycle.
jellyfish noj li cas?
Jellyfish, vim lawv txoj kev ua neej nyob hauv planktonic, yog tsiaj txhu Nyob rau hauv lawv cov tentacles peb pom nematocysts, hlwb uas muaj cov tshuaj ntsiav sab hauv (cnidocyst.) ntim nrog cov stinging kua thiab filament Nws raug rho tawm los ntawm cilia (cnidocilium) rhiab heev rau kev sib cuag.
Thaum tus ntses tau ze rau ntawm jellyfish thiab maj mam txhuam tawm tsam ib qho ntawm nws cov tentacles, cov nematocysts tau qhib, lawv raug ntiab tawm ntawm lawv cov tshuaj ntsiav thiab tso rau hauv qab ntawm daim tawv nqaij ntawm cov tsiaj, immobilizing nws. Ib zaug cov tsiaj txhu txav tsis tau, nrog kev pab ntawm cov tentacles, nws txav mus rau lub qhov ncauj thiab, los ntawm qhov ntawd, nws nkag mus rau hauv lub plab zom mov.
Kev tsim tawm ntawm jellyfish thiab polyps
Yuav kom nkag siab txog kev tsim cov tsiaj no peb yuav tsum xub paub tias cov jellyfish nyob qhov twg. Txhua hom cnidarian nyob hauv dej hiav txwv, ntsev los yog dej tshiab. Nyob rau hauv ib puag ncig zoo li no, fertilization sab hauv (kev sib koom ua ke ntawm lub qe thiab cov phev tshwm sim hauv cov poj niam) tsis yog qhov tshwm sim, yog li cnidarians muaj fertilization sab nraud Poj niam thiab txiv neej tso cov qe thiab cov phev mus rau sab nrauv, feem. Hauv hom hermaphroditic, ib tus neeg yuav tso ob lub qe thiab phev.
Raws li peb tau hais ua ntej hauv tsab xov xwm, muaj cov tsiaj uas tsuas muaj daim ntawv polyp, hom nrog daim ntawv medusa thiab hom nrog ob hom. Lawv feem ntau yog hermaphrodites Lwm hom yog dioecious thiab muaj kev sib deev. Yog li, cov tsiaj zoo li polyp tso cov gametes mus rau hauv ib puag ncig, tsim cov fertilization tom qab ntawd, ua rau cov larva, uas yuav nyob dawb kom txog thaum nws adheres rau seabed hauv daim ntawv, dua, ntawm ib tug polyp.
Thaum ib hom muaj ob hom hauv nws lub neej voj voog, cov polyps los ntawm strobilation (ib hom ntawm asexual reproduction) tsim jellyfish, thaum lawv loj hlob, tso cov gametes uas, raws li nyob rau hauv cov ntaub ntawv dhau los, yog. lawv fertilize ua ib tug larva uas yuav xaus ua ib tug polyp thiab qhov no, los ntawm budding, yuav ua rau ib tug tag nrho colony ntawm polyps.
Lwm qhov xwm txheej, qe tsim los ntawm gametes tso tawm los ntawm jellyfish tsis ua rau ib tug larva uas yuav xaus rau kev tsim. Ib tug polyp, Xwb, ib tug jellyfish tawm ncaj qha los ntawm lub qe, yog li ntawd lub polyp theem yog inhibited.
Jellyfish Curiosities
Raws li koj tau pom, kev tsim tawm ntawm jellyfish yog, tsis muaj kev poob siab, zoo heev. Cov tsiaj no muaj kev xav tsis thoob. Piv txwv li, nws yog tib pab pawg muaj peev xwm tsim cov qauv macroscopic geological pom los ntawm qhov chaw: coral reefs (Order Scleractinia).
Lawv yog tsim los ntawm 95% dej thiab tsuas yog 5% cov ntaub ntawv, vim li no lawv feem ntau hu ua "aguamalas" los yog "aguavivas"
Muaj ib hom jellyfish, Turritopsis Nutricula, yog ib yam tsiaj uas nyob tau ntev tshaj plaws thiab peb hu tau immortal, txij li thaum nws mus txog nws cov neeg laus theem ntawm "medusa" nws muaj peev xwm rov qab mus rau polyp, tuaj yeem rov ua cov txheej txheem no tsis kawg lub sijhawm.
