Reproduction yog ib tug txheej txheem tseem ceeb nyob rau hauv tag nrho cov hom uas nyob rau hauv lub ntiaj teb no, vim hais tias cov txheej txheem no yog dab tsi guarantees nws permanence. Cov kev tshwm sim kev yug me nyuam tsis yog dav dav hauv cov tsiaj ntiaj teb, ntawm qhov tsis sib xws, nyob rau hauv txhua pab pawg muaj ntau yam sib txawv uas tau tsim nyob ntawm tus yam ntxwv ntawm hom thiab ib puag ncig uas nws nyob vim tias tom kawg ua lub luag haujlwm tseem ceeb.
Hauv kev yug me nyuam peb pom fertilization, uas tau muab faib ua ob hom, sab hauv thiab sab nraud, txhua qhov tshwj xeeb thiab tshwm sim hauv ntau pawg tsiaj. Nyob rau hauv tsab xov xwm no ntawm peb lub xaib, peb xav qhia koj txog cov ntaub ntawv hais txog tsiaj muaj lwm yam fertilization, yog li ntawd peb caw koj nyeem ntxiv txog lub ntsiab lus nthuav.
fertilization sab nraud yog dab tsi?
Fertilization yog kev sib koom ua ke ntawm poj niam thiab txiv neej gamete, tseem hu ua ovules thiab phev, los ntawm qhov zygote thiab tom qab lub embryo yuav pib. Cov txheej txheem fusion no ntawm ob lub hlwb tuaj yeem tshwm sim hauv poj niam lub cev lossis sab nraud ntawm nws thiab, nyob ntawm nws, hu ua fertilization sab hauv lossis sab nraud. Yog li, sab nraud fertilization yog txheej txheem ntawm kev sib koom ua ke ntawm gametes sab nraum lub cev ntawm tus poj niam, kom nws tshwm sim nyob rau hauv ib puag ncig uas ob leeg tsiaj. Cov lus hais saum toj no qhia tau hais tias cov xwm txheej ntawm qhov chaw fertilization yuav tsum tsim nyog, vim hais tias txwv tsis pub cov txheej txheem yuav raug txwv los yog tiv thaiv.
Nyob rau hom fertilization peb tuaj yeem hais txog cov tsiaj txhu oviparous, uas yog, cov qe tsim tawm sab nraud niam lub cev. Nyob rau hauv cov tsiaj uas muaj hom kev yug me nyuam no muaj qee qhov nrog rau kev yug me nyuam, ib yam li cov noog, tab sis kuj tseem muaj oviparous nrog lwm cov fertilization, xws li qee cov ntses, thiab lwm yam. Tam sim no ces, cov yam ntxwv ntawm lub qe sib txawv nyob ntawm seb hom fertilization ntawm tus tsiaj:
- Cov oviparous hom nrog fertilization sab hauvmuaj qe tawv, nrog npog los yog plhaub tiv taus desiccation, yog li lawv tuaj yeem nyob sab nraum lub Dej.
- Cov cov tsiaj txhu uas muaj oviparous nrog lwm cov fertilization tsim qe tsis muaj kev tiv thaiv, muaj nyias nyias, yog li lawv feem ntau xav tau cov dej nyob ib puag ncig los yog cov av noo. ib puag ncig rau nws txoj kev loj hlob.
Qhov txawv ntawm qhov npog ntawm ib qho thiab lwm qhov kuj qhia tau tias, ntawm qhov qub, txij li lub qe tawm los twb tau fertilized, nws yog npaj rau kev loj hlob, thaum nyob rau hauv lub yav tas los nws yuav tsum tseem. tshwm sim cov fusion ntawm gametes, xav tau ib lub hau me me uas tso cai rau cov txheej txheem fertilization.
Vertebrates with external fertilization
Txawm hais tias kev fertilization sab hauv yog muaj nyob rau hauv ntau vertebrates, kuj muaj ntau hom vertebrates nrog lwm fertilization, uas muaj peev xwm nrhiav tau ntawm qee hom ntses thiab amphibiansTom ntej no, cia peb saib cov piv txwv ntawm vertebrates nrog lwm fertilization:
Ntses nrog fertilization sab nraud
Ntses yog cov tsiaj hauv dej uas nyob hauv dej hiav txwv thiab dej ntsev. Lawv yog ib pab pawg neeg sib txawv, tsis tsuas yog los ntawm ib tug taxonomic taw tes ntawm view, tab sis kuj nyob rau hauv cov nqe lus ntawm cov yam ntxwv lawv tam sim no. Hais txog fertilization, ntau hom ua cov txheej txheem sab nraud, txawm li cas los xij, nws yog qhov zoo heev, vim muaj ntau yam uas ua rau nws tawm tsam.
Ntawm ib sab, cov dej ib puag ncig nws tus kheej tuaj yeem ua qhov cuam tshuam rau ob lub qe thiab cov phev. Ntawm qhov tod tes, gametes muaj lub neej luv luv, yog li fertilization yuav tsum tshwm sim sai li sai tau, ntxiv rau, cov phev me me muaj qhov txwv kom ncav cuag gamete. poj niam. Tsis tas li ntawd, peb yuav tsum hais tias ntau hom tsiaj pub rau cov qe tso tawm los ntawm cov poj niam, tab sis, txawm hais tias txhua yam hais, lub neej ntawm pawg tsiaj no tseem nyob ntawm nws txoj kev thiab lawv tswj kom rov tsim tau zoo.
Thov daws cov lus saum toj no, cov tsiaj hauv dej uas muaj cov fertilization sab nraud yog muab nrog ib yam dab tsi hu ua chemotactic factor, uas muaj cov tshuaj lom neeg tso tawm los ntawm ova kom nyiam txiv neej gametes Cov tebchaw no tshwj xeeb rau txhua hom. Nws kuj yog ib qho ua rau spawning loj heev los sim ua kom muaj feem ntau uas qee tus yuav tswj tau los txhim kho.
Ntawm cov ntses uas muaj fertilization sab nraud peb tuaj yeem hais:
- European perch (Perca fluviatilis)
- Atlantic cod (Gadus morhua)
- Brook trout (Salvelinus fontinalis)
- Pink salmon (Oncorhynchus gorbuscha)
Amphibians with external fertilization
Nyob rau hauv amphibians muaj ntau yam piv txwv ntawm cov tsiaj uas muaj lwm yam fertilization, txawm hais tias nws tsis yog ib tug kiag li txoj cai vim hais tias kuj muaj hom ntawm no hom uas nqa tawm lwm yam fertilization.
Ntawm cov hom amphibian nrog rau sab nraud fertilization peb pom:
- Nkauj Noog Hawj (Nkauj Hmoob)
- Minor Siren (Intermediate Siren)
- Qab Qav (Rana temporaria)
- Suav loj salamander (Andrias davidianus)
- Fischer's clawed salamander (Onychodactylus fischeri)
Invertebrates with external fertilization
Nyob rau hauv invertebrates peb kuj pom ntau pawg tsiaj nrog sab nraud fertilization, qhov tseeb, nws yog heev muaj nyob rau hauv hom tsiaj no inhabitants nyob rau hauv dej. Txawm hais tias tej zaum yuav muaj qee yam tshwj xeeb hauv txhua pab pawg, vim qee qhov muaj lub neej tsis muaj zog thiab lwm tus tsis ua, cov txheej txheem feem ntau zoo ib yam: cov tsiaj yuav tsum tso lawv cov gametes rau hauv dej kom lawv fuse thiab tshwm sim fertilization, ces, ib tug series ntawm transformations yuav tshwm sim los ntawm embryonic daim ntawv.
Cov tsiaj txhu uas muaj kab mob sab nraud kuj raug cuam tshuam los ntawm ib puag ncig, uas tuaj yeem txwv lossis txwv tsis pub cov txheej txheem tshwm sim, tab sis ntau zaus lawv kuj tswj kom kov yeej lawv thiab ua tiav cov noob qoob loo. Piv txwv ntawm invertebrates nrog fertilization sab nraud yog:
Mollusks
Nws yog ib txwm muaj rau hom dej molluscs kom muaj cov fertilization sab nraud thiab qee qhov piv txwv feem ntau yog:
- Clam (Mercenary Mercenary)
- Pacific Oyster (Magallana gigas)
Echinoderms
Rau cov echinoderms uas fertilized sab nraum tus poj niam lub cev, peb tuaj yeem hais cov piv txwv hauv qab no:
- Common Starfish (Asterias rubens)
- Donkey manure (Holothuria mexicana)
Arthropods
Nyob rau hauv pab pawg ntawm marine arthropods peb pom tej yam piv txwv ntawm hom fertilization no, ntawm cov uas peb highlight:
- Hiav txwv kab laug sab (Pycnogonum littorale)
- American Horseshoe Crab (Limulus Polyphemus)
Hiav txwv anemones thiab corals
Nyob hauv pab pawg tsiaj no tshwj xeeb hauv dej, fertilization sab nraud muaj ntau, yog li peb tuaj yeem hais:
- Knotty Brain Coral (Pseudodiploria clivosa)
- Elkhorn Coral (Acropora palmate)
Polychaetes
Polychaetes yog segmented worms ntawm Annelid phylum. Lawv sib haum mus rau ntau haiv neeg ntawm polychaetes, feem ntau yog nyob rau hauv marine ib puag ncig. Fertilization ntawm tag nrho pawg yog sab nraud.
Vim li cas cov tsiaj hauv dej feem ntau ua rau lwm tus fertilization?
Tsiaj txhu, tsis muaj qhov tsis ntseeg, dhau ntawm lawv cov txheej txheem hloov pauv thiab hloov pauv, tsim cov txheej txheem sib txawv lossis cov tswv yim uas muaj txiaj ntsig zoo rau lawv lub neej. Cov dej nyob ib puag ncig muaj peev xwm los tsim cov gametes rau fertilization tshwm sim, ib yam dab tsi uas tsis tshwm sim nyob rau hauv lub terrestrial ib puag ncig, yog li ntawd hauv cov dej fertilization yog ua tau yam tsis muaj tsiaj kov
Ntawm qhov tod tes, tom qab fusion ntawm ovules thiab phev, qhov chaw hauv dej kuj muaj qee qhov zoo dua, muaj peev xwm ntawm kev tawg ntawm cov zygote tshiab. Raws li peb tau hais lawm, cov tsiaj no tso tawm ntau lub qe rau hauv dej, nyob rau hauv xws li ib txoj kev uas ciaj sia taus ntawm cov tsiaj yog guaranteed ob qho tib si los ntawm ntau thiab tsawg dispersion muab los ntawm ib puag ncig. Thaum muaj ntau hom kev loj hlob nyob rau hauv hom chaw nyob nrog cov muaj peev xwm fertilize, lawv siv nws rau lawv cov txiaj ntsig, uas yog vim li cas evolution tau tso cai rau lawv hom kev loj hlob no.