Lophotrochozoa vs Ecdysozoa
Qhov sib txawv ntawm lophotrochozoa thiab ecdysozoa, ob qho tib si loj, tau tham hauv kab lus no. Raws li cov kev tshawb fawb tsis ntev los no siv nuclear thiab mitochondrial DNA sequences, cov kws tshawb fawb tau hloov kho lub taxonomy ntawm Tsiaj Kingdom. Raws li cov tshiab molecular phylogenies, cov kws tshawb fawb txheeb xyuas cov deutersomes ua ib pawg ntuj tsim. Ntxiv mus, pawg loj ntawm protostomes tam sim no tau muab faib ua ob pawg monophyletic bilaterian hu ua Lophotrochozoa thiab Ecdysozoa. Li no, Tsiaj Nceeg Vaj tam sim no muaj peb qhov loj monophyletic clades ntawm ob sab tsiaj; Lophotrochozoa, ecdysozoa, thiab deuterstomia. Lub clade dueterostomia ntxiv muab faib ua ob pawg; (a) ambulacraria, uas suav nrog echinoderms, thiab (b) chordate, uas muaj urochordates, cephalochordates thiab vertebrates. Lophotrochozoa thiab ecdysozoa tau muab faib ua ntau thiab ntau pawg raws li lawv cov molecular phylogenies.
Lophotrochozoa yog dab tsi?
Cov yam ntxwv ntawm cov pab pawg lophotrochozoa yog qhov muaj cov trochophore larvae thiab cov qauv pub mis hu ua lophophore. Txawm li cas los xij, tsuas yog ob peb lophotrochozoans muaj ob qho ntawm cov yam ntxwv no. Lophotrochozoans yog kev sib deev los ntawm kev tso lawv cov gametes rau hauv ib puag ncig. Asexual reproduction kuj muaj nyob rau hauv pawg no. Txhua tus tswv cuab ntawm pab pawg no yog triploblastic thiab qhia tau hais tias ob tog symmetry. Ob qho tib si terrestrial thiab dej muaj nyob hauv pawg no. Lophotrochozoa tau muab faib ua rau pawg sub; (a) Flatworms (Platyhelminthes, uas suav nrog turbellarians, trematodes, thiab cestodes), (b) Nemerteans (ribbon worms), Mollusks (chitons, gastropods xws li qwj, slugs, nudibranchs, bivalves zoo li clams thiab oysters, cephalopods thiab cephalopods.), (c) Annelids (polychaetes zoo li sandworms thiab tubeworms, oligochaetes nrog rau cov kab mob hauv av thiab cov kab mob dej tshiab, hirudinids, uas suav nrog cov kab mob leeches), (d) Lophophorates (branchipods, phoronids, thiab bryozoans), thiab (e) Rotifera (cov tsiaj txhu).
Ecdysozoa yog dab tsi?
Lub npe ecdysozoan tau muab rau cov tsiaj no vim muaj cov tshuaj steroid tshwj xeeb hu ua ecdysteroids, uas tswj cov txheej txheem hu ua ecdysis lossis metamorphosis. Ecdysozoans muaj lub cev pob txha pob txha thiab tuaj yeem tso cov pob txha los ntawm ecdysis. Feem ntau ntawm cov tswv cuab hauv pab pawg no muaj kev sib deev sib txawv. Thaum lub sij hawm cev xeeb tub, txiv neej tso phev nyob rau hauv lub cev ntawm tus poj niam. Ntau yam ecdysozoans yog hom nyob ib leeg, hos qee hom nyob hauv cov cheeb tsam. Qee hom qhia tias kev yug me nyuam tsis zoo los ntawm parthenogenesis.
Cov pab pawg tseem ceeb ntawm ecdysozoan suav nrog nematodas (roundworms), onychophorans (velvet worms), tardigrades ("dej bears"), thiab arthropods. Phylum Arthropoda yog pawg loj tshaj plaws uas muaj ntau hom tsiaj thiab muaj xws li myriapods (centipedes, millipedes), chelicerates (horseshoe crabs, arachnids), crustaceans (lobsters, crabs, barnacles, copepods), thiab hexapods (kab kab).
Qhov txawv ntawm Lophotrochozoa thiab Ecdysozoa yog dab tsi?
• Ecdysozoans muaj peev xwm tso lawv cov exoskeleton ob peb zaug thoob plaws hauv lawv lub neej, whereas lophotrochozoan yog cov tsiaj uas muaj trochophore larvae thiab cov qauv pub mis hu ua lophophore.
• Tsis zoo li lophotrochozoan, ecdysozoans muaj cov tshuaj steroid tshwj xeeb hu ua ecdysteroids.
• Ecdysozoa suav nrog nematodes, arthropods, onychophorans, thiab tardigrades, whereas lophotrochozoan muaj xws li flatworms, nemerteans, mollusks, annelids, lophophorate, thiab rotifer.
