Fossil cnidarians tau pom nyob rau hauv pob zeb tsim kwv yees 580 lab xyoo dhau los, thiab lwm cov pob txha qhia tau tias corals tuaj yeem tshwm sim sai ua ntej 490 lab xyoo dhau los thiab muaj ntau haiv neeg ob peb lab. xyoo tom qab.
thawj cnidarian yog dab tsi?
Lwm txoj kev xav yog tias tus thawj cnidarian yog ib hom kab mob zoo li cov kab mob uas ua ntej ob qho tib si polyp thiab medusa Txawm li cas los xij, Hydrozoa tau suav tias yog qhov qub tshaj plaws ntawm cov chav kawm cnidarian, thiab Trachylina tau xav tias yog qhov kev txiav txim qub tshaj plaws ntawm pawg ntawd.
pab pawg twg cnidarians hloov zuj zus los ntawm?
Fortuitously, thawj ob cnidarian genomes yuav tsum tau sequenced los ntawm Anthozoa (Nematostella) thiab Hydrozoa (Hydra); Cov poj koob yawm txwv kawg ntawm ob chav kawm no yog qia cnidarian (Fig. 1).
Cnidarians thawj zaug ua dab tsi?
Cnidarians yog thawj tus tsiaj rau muaj cov leeg thiab paj hlwb tsim tus cwj pwmLawv kuj yog thawj tus muaj qhov ncauj thiab plab zom zaub mov. Peb kawm txog nematocysts thaum peb saib anemone ntes tus goby thiab ob anemones sib ntaus. Cnidarians tuaj ntau lub cev thiab muaj ntau txoj kev nyob.
cnidarians tuaj qhov twg?
Lub npe Cnidaria los los ntawm Greek lo lus "cnidos," uas txhais tau tias stinging nettle. Casually kov ntau cnidarians yuav ua kom paub tseeb tias lawv tau txais lawv lub npe thaum lawv cov nematocysts eject barbed threads tipped nrog tshuaj lom.
