Izici zesakhiwo se-gamete
Amaseli ezocansi, uma eqhathaniswa nesimo esivamile, somatic, unemibono eminingi. Okubaluleke kakhulu kulawa yi-haploid iqoqo lama-chromosomes, elitholakala ngqo kwi-nuclei yamaseli wesondo ngokwawo. Lokhu kuqinisekisa ukukhiqizwa kwi-zygote yeqoqo elivamile le-diploid ye-chromosomes yezinto eziphilayo, okungukuthi. isigamu somama, isigamu sikayise.
Futhi ama-gametes ahlukile kwamanye amaseli ngobuhlobo obungavamile phakathi kwe-nucleus ne-cytoplasm. Ngaphezu kwalokho, ngo-spermatozoa kuphakeme kunama-oocyte. Lokhu ngokuyinhloko ngenxa yokuthi in spermatozoa inani le-cytoplasm lincane, uma liqhathaniswa ne-ovule, equkethe inani elikhulu lazo izakhi ukuze kuthuthukiswe umbungu.
Ngaphezu kwalokho, ngokungafani namaseli angama-somatic, amangqamuzana ezocansi abonakala ngezinga eliphansi lezinqubo zokuqubuzana.
Iyini imisebenzi yamaseli wesilisa wesilisa?
Okuyinhloko futhi, mhlawumbe, umsebenzi owodwa we-spermatozoa, ukuzala. Isibindi, ukuhlangana neqanda, ubanikeze ngeqoqo labo lama-chromosomes, okudingekayo ekuthuthukiseni umbungu.
Iyini imisebenzi yamaseli wesifazane omzimba?
Uma kuqhathaniswa neseli lesiduna lesilisa ngokobulili, imisebenzi yakhe ihlanganisa kuphela ukukhulelwa kweqanda kanye nokuhlinzekwa kwezinto eziphilayo, amangqamuzana abesifazane okuzala adlala indima enkulu ekukhulelweni.
Ngakho-ke, yiqanda elihlinzeka i-fetus enezakhi esikhathini esizayo, yenza umsebenzi we-trophic, ngaphezu kwalokho, igobolondo leqanda ngaphambi kokubunjwa kwe-zygote futhi kwenza umsebenzi wokuzivikela.