Ukufakela umquba - yintoni na kwaye kwenzeka ntoni? Ukuchumisa kabini kwiintlobo zezimbali

Ukufakelwa kwemfuyo yinkqubo yokuhlanganiswa kwamaseli amabini, okwenza ukuba kusetyenziswe iseli elitsha elivelisa enye inxalenye yesityalo okanye uhlobo olufanayo. Yintoni ukuchumisa kabini kwizityalo eziqhakazelisayo? Izityalo kunye nokuba kwenzeka ntoni, funda eli nqaku.

Ingundoqo yokuchumisa

Iyenzeka ngenxa ye-fusion yamaseli amabini, isetyhini kunye nendoda, kunye nokubonakala kwe-dipyidide zygote. Kwiqela ngalinye lama-chromosomes, kukho enye yesibini kunye nesinye iseli somama. Ingundoqo yenkqubo yokuchumisa ukubuyisela i- diploid isethi yama-chromosomes kunye nokudibanisa izinto ezizalwe ngabazali. Inzala yabo iya kuba namandla ngakumbi, njengoko iya kudibanisa iimpawu ezinobulumko kakhulu kubazali nonina.

Umquba - yintoni na?

Le yinkqubo yokunciphisa iqanda ukuphuhlisa njengesiphumo sokuhlanganiswa kweenucleuclei. Umquba - yintoni na? Le yinkqubo engenakuguqulwa eyenzeka ngenxa ye-fusion yegetet ye-heterogene kunye nomanyano we-nuclei yabo. Iqanda elichumisiweyo alixhomekeke kule nkqubo yesibini.

Kodwa kukho izityalo ezizalisa isizukulwana esitsha kuphela ngoncedo lwamagetethe amabhinqa ngaphandle kokuchumisa. Ukuveliswa okunjalo kubizwa ngokuthi intombi. Kuyaphawuleka ukuba ezi ndlela ezimbini zokuvelisa kwisityalo esinye sinokuthi zenze enye.

Ukuchumisa kabini izityalo zezimbali

Iiseli zesini zombini zombini zibizwa ngokuba yi-gametes. Kwaye amaqanda amabhinqa angowesifazana, kwaye iindoda ziyi-spermatozoa, ezingenasiphelo kwizityalo zembewu, ngelixa zityalo zitshatsheli zihamba. Umquba - yintoni na? Oku kubonakala kwiseli ekhethekileyo - i-zygote, equle iimpawu zokuzalwa zesidoda kunye ne-ovum.

Izityalo eziqhaqhaqhokazi zinomsoco obunzima, obizwa ngokuba kabini, ekubeni, ngaphezu kweqanda, enye iseli ekhethekileyo ixutywe. Ukwenziwa kwe-spermatozoa kwenzeka othulini lwe-pollen, kwaye ukuvuthwa kwabo kuqhutyelwa kwi-stamens, ngokuchanekileyo kwi-anthers yabo. Indawo yokubunjwa kweqanda i-ovipules e-ovary ye-pestle. Xa iqanda lihlanganiswe nesidoda, imbewu iqala ukuphuhla kwi-ovule.

Ukuze uzalise izityalo zezimbali, okokuqala kufuneka utyilise isityalo, oko kukuthi, kwi-stigma ye-pistil kufuneka ufumane i-speck ye-pollen. Ngesinye isihlamba, baqala ukuhluma ngaphakathi kwe-ovary, okubangela ukuba kwakhiwe ityhubhu ye-pollen. Ngexesha elifanayo, i-spermatozoa emibini yenziwa kwi-speck of dust. Abayimi, kodwa baqale ukuhamba kwiphubhu ye-pollen, engena kwi-ovule. Apha, ngenxa yesahlulo kunye nokwandiswa kweeselinye enye, ifom ye-sac embrasi.

Kuyimfuneko ukuba indawo kwindawo yeqanda kunye nelinye iseli apho iqoqo eliphindwe kabini leenkcukacha zobomi ligxininiswe. Emva koko, ityhuphu ye-pollen ihluma ibe yesikhwama se-embryonic kwaye idibanisa enye imbumba kunye neqanda, leyo ibangela ukubunjwa kwe-zygote, kunye nelinye iseli ekhethekileyo. Uphuhliso lombungu luvela kwi-zygote. I-fusion yesibini ivelisa izicubu zesondlo, okanye i-endosperm, kuyimfuneko ekudleni umbungu ngexesha lokukhula.

Yintoni efunekayo ukuze kubekho iintlobo zezityalo nganye?

• Okokuqala, kuyimfuneko ukubuyisela i-diploid isethi yama-chromosomes, kunye nemida yayo - iibini zazo.
• Qinisekisa izinto eziqhubekayo phakathi kwezizukulwana, ukulandelelana okulandelayo.
• Hlanganisa ngenye indlela okanye ngesini iipropati zabazali ababini.

Konke oku kwenziwa kwinqanaba lemfuza. Ukuze ukuchumisa kuqhutywe, ukuveliswa kwamagetetti omama kunye noomntwana kufuneka kwenzeke kanyekanye.

Ukufakelwa kwemfuyo kwii-angiosperms

Le nkqubo yaqala ngokuchazwa ngumsululwazi waseJamani u-Strasburger kwisiqingatha sesibini senkulungwane yeshumi elinesithoba. I-angiosperms ye-Fertilization ivela ngenxa ye-fusion ye-nuclei ye-gametes eyahlukeneyo: kunye nabesilisa nabesifazane. I-cytoplasm yabo ayinathathi inxaxheba kwisichumiso. Ukuqumba kwangoku kwenzeka xa idiza idibanisa kunye nomxholo weqanda.

Indawo yokuvela kwi-spermatozoa yi-pollen grains okanye i-tublen tubes. Ingqolowa iqala ukuhluma emva kokuba ifinyelele ihlazo. Ixesha lokuqala le nkqubo kwisityalo ngasinye siyahluke, njengokuba ixesha lokuchumisa. Ngokomzekelo, imbewu ye-beet ye-pollen ihluma ngeeyure ezimbini, kunye nommbila-kwangoko. Umqondiso wokuqala wokuhluma kwengqolowa kukunyuka kwindleko. Ngokuqhelekileyo inkozo eyodwa yempepho yenza ityhubhu enye. Kodwa ezinye izityalo aziwuthobeli lo mgaqo kwaye zenze iibhubhu ezininzi, apho enye kuphela ifinyelela ukuphuhliswa kwayo.

I-tube ye-pollen enobudoda ehamba kunye nayo ikhula kwaye ekugqibeleni iphule. Zonke iziqulatho zalo zingaphakathi kwesikhwama sombungu. Esinye sezidoda esangene apha siqaliswa kwiqanda kwaye sidibanisa ne-haploid nucleus. Umquba - yintoni na? Oku kukuhlanganiswa kwee-nuclei ezimbini: i-sperm kunye ne-ovum. Iqanda elichumayo liqala ukwahlula, kufumaneka iiseli ezimbini ezintsha. Zihlukaniswe zibe ezine kunye njalo. Ngaloo ndlela, ukwahlukana kwahlukeneyo kubakho, ngenxa yoko umbungu wesityalo ukhula.

IAngiosperms emva kokuba inkqubo yokuchumisa inakho ukuphuhlisa ilungu elongezelelweyo elibizwa ngokuba yi-endosperm. Oku akusiyo kodwa umgangatho wesondlo we-embryo. Xa isibini sesibini kunye ne-diploid nucleus idibanisa, kusekwa isethi echanekileyo yama-chromosomes, apho ezimbini zivela kwimvelaphi yomzali, kunye nenye yobawo. Ngaloo ndlela, ukuchumisa kabini kwezidalwa zezityalo kwenzeka xa omnye umntu edibanisa neqanda kunye nomnye kunye nenucleus yeseli ephakathi.

Iimpawu ezahlukileyo ze-angiosperms

• Ukulungelelanisa ngakumbi ukukhula kwiimeko ezahlukeneyo.
• Ukutsalwa kwezichumiso, ukuvumela ukuba inesitokethi sezinto eziyimfuneko ukuhluma okuqhelekileyo kwembewu.
• Ubukho be-endospid endosperm.
• Ukwakhiwa kwe-ovules ngaphakathi kwe-ovary, apho izindonga ze-pistil zibavikela kumonakalo.
• Ukuphuhliswa komntwana we-angiosperms ukusuka kwi-ovary.
• Ukufumana imbewu ngaphakathi kwesiqhamo, iindonga zazo ziyakhusela.
• Ubukho beentyatyambo kwenza kube lula ukuvelisa izityalo ezinambuzane.

Ngenxa yeziganeko ezichazwe kwii-angiosperms zihlala kwindawo ephezulu kwihlabathi.

Ubunqabileyo bokusatshalaliswa kwama-angiosperm

Kuya kuvela kwinto yokuba ezi zityalo ziqulethwe kabini. Into eyingqayizivele imelwe yinto ebizwa ngeXenia. Intsikelelo yalo ikhona kwinto yokuba impova ichaphazela ngqo iimpawu kunye neempawu ze-endosperm. Umzekelo, thabatha ingqolowa.

Kwenzeka ngeembewu eziphuzi kunye ezimhlophe. Umbala wabo kuxhomekeke kumthunzi we-endosperm. Xa i-pollination yeentyantyambo zentombi zommbila omhlophe omhlophe kunye ne-pollen yoluhlu oluluhlaza, umbala wayo uya kusasa, nangona uphuhliso lwe-endosperm lwenzeka kwisityalo esinomqolo omhlophe.

Iyiphi indima yezityalo eziqhambileyo?

Ezi zityalo zinemiqolo engama-13 000 kunye neentlobo ezingama-250,000. Zisasazwa jikelele kwihlabathi. Iintlobo zezimbali ziyinxalenye eyintloko ye-biosphere, ukuvelisa izinto eziphilayo ezibopha i-carbon dioxide nokukhupha oksijini. Ukutya iintambo zokutya ziqala nabo. Zininzi iintlobo zezityalo eziqhakazileyo abantu basebenzisa ukutya. Bakha izindlu kunye nokwenza izinto ezahlukeneyo zendlu.

Musa ukwenza ngaphandle kwabo kunye namayeza. Iintlobo zee-angiosperm ezizimeleyo zilawulwa kwiplanethi, zinikwe indima ebalulekileyo ekuvelweni kwendawo yokugcina izityalo kunye nokudala inxalenye ephambili ye-phytomass yomhlaba. Ekugqibeleni, zezi zityalo ezenza ukuba kubekho ubukho bomntu emhlabeni njengentlobo yezinto eziphilayo.