Ukuvundisa - kwenzekani futhi kanjani? kokukhulelwa Double e izimbali

Ukuvundisa - yinqubo ukuhlanganisa amaseli ezimbili, okuphumela ekwakhiweni amangqamuzana amasha, futhi isishiya omunye umzimba bohlobo lwe-efanayo noma zilwane. Uyini kokukhulelwa double e izimbali isitshalo futhi kwenzeka kanjani, ukufunda lesi sihloko.

Ingqikithi sokukhulelwa

Kuziwa ngenxa Fusion lamaseli ezimbili, kwabesifazane nabesilisa, futhi kwavela zygote diploid. Ngo pair wama-chromosomes ngamunye okhona zoyise nelilodwa ingqamuzana kwabakhulelwe. Ingqikithi inqubo fertilization ukubuyisela isethi diploid wama-chromosomes futhi sihlanganise zofuzo zabazali. nenzalo yabo bayojabula iphila ngaphezulu njengoba ngokuhlanganisa izimfanelo ziwusizo ikakhulu kusukela uyise nonina.

Ukuvundisa - kuyini?

Le nqubo esibatshela ukuthuthukiswa amaqanda e nokuhlanganiswa nuclei. Ukuvundisa - kuyini? Lena inqubo okungenakuhlehliswa okuyinto eyenzeka ngenxa Fusion gametes of abesilisa nabesifazane ezahlukene bese kuhlanganiswa inchumbi nuclei yabo. Iqanda avundiswa akuyona ngale nqubo okwesibili.

Kodwa zikhona izitshalo ukuthi ukukhiqiza kabusha isizukulwane esisha kuphela gamete besifazane ngaphandle kokukhulelwa. Lokhu ukukhiqizwa kabusha ibizwa ngokuthi intombi. Kuyaphawuleka ukuthi lezi zindlela ezimbili zokukhiqiza kabusha kwelinye uhlobo esimileni, singasetshenziswa esikukhompiyutha.

kokukhulelwa Double zezimbali

Ubulili amaseli kokubili waqala ubizwe gametes. Futhi abesifazane kukhona amaqanda, futhi iduna - isidoda Lowo otshalayo imbewu fixed, kuyilapho spore - ephathekayo. Ukuvundisa - kuyini? Akukhona ukubukeka yeseli esithile - the zygote, equkethe lezinceku izici isidoda neqanda.

Izimbali izitshalo babe kokukhulelwa eziyinkimbinkimbi, okuthiwa i-double, ngoba ngaphezu iqanda is avundiswa ngomunye esitokisini esikhethekile. Kumiswa isidoda senzeka zothuli impova, kanye nokuvuthwa yabo kwenziwe stamens, noma kunalokho ku anthers yabo. Spot kumiswa ovules amaqanda zitholakala pestle esibelethweni. Lapho iqanda is avundiswa isidoda, ovule zisuka ukuthuthukisa imbewu.

Ukuze kokukhulelwa e izimbali eyenzekile, okokuqala udinga ukuthi ungcolise isitshalo, okungukuthi, phezu hlazo okumelwe uthole Ucezwana ngothuli impova. Uma inhlamba, baqala ukukhula ngaphakathi esibelethweni, kuphumele tube impova. Ngasikhathi sinye, kwakheka kuyizinhlayiyana uthuli is lamaseli amabili isidoda. Abanaso yima unganyakazi futhi uqale iphokophele tube impova, okuyinto angena ovule. Lapha, ngokuyihlukanisa owodwa cell ukunwebeka kanye kumiswa sac umbungu.

It edingekayo ukuze indawo iqanda ke, ngisho kuseli eyodwa, egxile isethi kabili ukwaziswa kwezakhi zofuzo. Ngemva kwalokho impova ishubhu ukuhluma kwenzeka ngaphakathi komgodlana embungwini Fusion isidoda neqanda, okuphumela ekwakhiweni le zygote, kanye nezinye - ngengqamuzana ethile. ukuthuthukiswa umbungu kusuka zygote kwenzeka. I Fusion wesibili wakha izicubu nutritive, endosperm noma idingeka ukuze umsoco umbungu ngesikhathi ukukhula.

Okudingayo sokuba khona uhlobo isitshalo ngasinye?

• Okokuqala, udinga ukubuyisela isethi diploid wama-chromosomes, futhi ngaphakathi kuwo bekulokhu - ukubhanqa wabo.
• Nikeza embili impahla phakathi izizukulwane, kulandela ukulandelana.
• Hlanganisa ukwakha uhlobo olulodwa noma izakhiwo lezinceku bobabili abazali.

Konke lokhu kwenziwa ezakhini zofuzo. Ukuze kokukhulelwa waqaphela, ekukhuleni kwamangqamuzana gametes komama kanye zoyise Kuyothi kanyekanye.

Ukuvundisa e angiosperms

Le nqubo kuchazwa okokuqala usosayensi German Strasburger engxenyeni yesibili yekhulu nesishiyagalolunye. Kokukhulelwa kwenzeka angiosperms nokuhlanganiswa gametes ezimbili nuclei ezahlukene: ne besilisa isimiso zesifazane. cytoplasm labo akazibandakanyi kokukhulelwa. Empeleni Ukuvundisa kwenzeka uma isidoda fuses ne-nucleus amaqanda.

Lapho kwazalelwa Isidoda impova okusanhlamvu noma impova ishubhu. Okusanhlamvu uqala zikhule emva ukuwa phezu inhlamba. Isikhathi ekuqaleni kwale nqubo, isitshalo ngasinye sihlukile, njengoba ngesikhathi sokukhulelwa. Ngokwesibonelo, u-beetroot impova okusanhlamvu ziqhume ngemuva kwamahora amabili, nommbila - kweso. Uphawu lokuqala ukuhluma - ukwanda yayo ivolumu. omunye impova okusanhlamvu Ngokuvamile ingenye tube. Kodwa ezinye izitshalo awekho ngaphansi mthetho futhi yakha handsets amaningi, eyodwa kuphela zazo ifinyelela ukuthuthukiswa yayo.

Impova tube nesidoda ku ambulant yakhe ikhula futhi ekugcineni iphula. Konke okuqukethwe yayo luphakathi sac umbungu. Omunye infiltrators lapha isidoda is busuka iqanda okuhlanganisiwe ne-nucleus yayo haploid. Ukuvundisa - kuyini? Lokhu Fusion ezimbili nuclei we isidoda neqanda. Iqanda avundiswa iqala ukwehlukana, etholwe amaseli ezimbili ezintsha. Basuke uhlukaniswa kane, njalo njalo. Ngakho, kukhona ukwahlukana amaningi, lapho umbungu isitshalo eba.

izitshalo Angiosperm emva kokukhulelwa unekhono ukuthuthukisa umzimba ngokwengeziwe, othiwa endosperm. Kayisilutho ngaphandle izakhi umbungu ophansi. Ngezinye confluence yakheke isidoda yesibili futhi nucleus diploid ezithile-chromosomes, ezimbili zazo - imvelaphi komama kanye eyodwa - uyise. Ngakho, kokukhulelwa double isitshalo eziphilayo kulapho isidoda fuses iqanda, kanye nezinye - ne amaseli core, etholakala maphakathi.

izici esasenza angiosperms

• lithathelwe Okuningi okukhulisa ezimeni ezahlukahlukene.
• kokukhulelwa Double, okuvumela ukuba abe supply of izinto ezidingekayo ukuze ukuhluma ezivamile imbewu.
• Ukuba khona triploid endosperm.
• ovules Ezemfundo ngaphakathi esibelethweni, lapho izindonga carpel ukubavikela ekulimaleni.
• ukuthuthukiswa kwengane angiosperms kusukela esibelethweni.
• Ukuthola imbewu ngaphakathi izithelo, izindonga zazo ivikelwe ke.
• Ukuba khona izimbali kwenza kube nokwenzeka ungcolise izitshalo ezinambuzaneni.

Ngenxa yalezi zici angiosperms anesikhundla evelele emhlabeni.

Isici ukuzalanisa angiosperms

Ngakho kusukela lokuthi lezi zitshalo abe kokukhulelwa double. Isici eyingqayizivele imelelwa mkhuba ngokuthi Xenu. nencazelo yalo itholakala lokuthi ukuthi impova ezithinta ngqo izakhiwo kanye izici endosperm. Ngokwesibonelo, ukuthatha corn.

Kuyinto imbewu yellow nomhlophe. umbala wabo incike umbala endosperm. Ngemva impova izimbali insikazi impova Belozernaya ummbila izinhlobo zheltozernogo Umdwebo wakhe usazoba ophuzi, kuyilapho ukuthuthukiswa endosperm kwenzeka ku isitshalo ubhontshisi omhlophe.

Iyini indima eziqhakazayo?

akhawunti Lezi zitshalo for 13 000 ezizalwa 250 000 zilwane. Basuke kabanzi emhlabeni wonke. Izimbali zezitshalo - lezi izingxenye ezisemqoka we uHlu Jikelele Lwamakheli, ukukhiqiza izinto eziphilayo ezenza carbon dioxide futhi ihlaba umkhosi umoya-mpilo. Iklabile eziwukudla iqala kubo. Izinhlobo eziningi eziqhakazayo umuntu esebenzisa i-ukudla. Kulawa, bakha imizi nokwenza izinto ezihlukahlukene yasendlini.

Ayikwazi ukwenza ngaphandle kwabo, futhi imithi. Izinhlobo ezithile angiosperms abangelwa ngokuyinhloko emhlabeni, badlala indima juqu ukwakheka kanye ukusungulwa ikhava ezitshalweni ezisemhlabeni ingxenye eyinhloko phytomass phansi. Kakade lokhu kuyisinqumo lezi zitshalo kunqunywa kungenzeka abe khona yomuntu emhlabeni njengoba uhlobo begazi.