Gameti ndiwo masero ekubereka anonzi urume muvarume uye ovum mune vakadzi. Ivo vari mune dzepabonde gland, ayo anonziwo maGonads. Iwo maGonads muvanhurume ndiwo miedzo uye mune vanhukadzi iwo ari mazai. Isu tinotaura nezve "gamete", zita rechirume.

Izwi rekuti "gamete" rakagadzirwa kubva kumazita ekare echiGiriki, "γαμ? Της ”, mageteti uye“ μαμ? Τις ”, mageteti, ayo anoreva murume nemukadzi zvichiteerana.

Gametes masero e haploid, ndiko kuti, ane muunganidzwa wakazara wemachromosomes edu, mune imwe kopi imwe neimwe.

Mune vakadzi

Vakadzi mageteti, anonzi ova, anogadzirwa nemazai. Tine vaviri, mumwe kuruboshwe uye mumwe kurudyi. Mazai acho anoita zai rimwe pamwedzi. Iyi ovum ine kosi yakakomberedzwa ne cytoplasm, yakasungwa ne membrane. Ovha saka sero.

Aya maseru ekubereka, ane hupamhi hwe0,1 mm muhupamhi, ari haploid. Ivo vane kopi imwe chete yechromosome imwe neimwe, zvakapesana kune diploid sero, iro rine maviri mahemologi echromosome imwe neimwe. Iwo ane makumi maviri neshanu echromosomes + 22 bonde chromosome). Vakadzi mageteti anogadzirwa panguva ye oogenesis, iyo ovari kutenderera, iyo nguva iri pakati penguva yekuenda kumwedzi.

Asati akura, mukadzi ane izvo zvinonzi ovarian follicles. Iyo inoungana yemasero madenderedzwa mumazai, iine izvo zvinodaidzwa kuti oocyte, (zai risina kuumbwa) rinoburitswa panguva yekuvhara.

Izvo zvinongova pakuyaruka apo iyo follicles inoenda mukukura kwavo kwakakodzera kune ovulation, ivo vanobva vawedzera saizi. Mazai acho anoshanda nguva dzese uyezve anoburitsa zai.

Nekudaro, mwedzi wega wega, ovarian follicle inokura, mune imwe kana imwe ovary, isati yaburitsa zamu rayo: isu tinobva tataura nezve ovulation. Ichi chinoshamisa, chinodzokororwa mwedzi wega wega, kana pasina kusangana, saka chiri cyclical, sekumwedzi.

Zai harifambe uye igameti inonamira. Kana pakange pasina kusangana, zai rakaburitswa neiyo ovary rinoswededzwa kuburikidza nepini yeproboscis uye rinodhonzwa zvisina basa. Inopfuura nepakati pechibereko ichibva yabviswa nehana.

Munguva yehupenyu hwake, mukadzi anoburitsa huwandu hwakawandisa hwemazai, kutenderedza mazana mana. Kugadzirwa kwemazai, pamwe chete nenhambo dzinomira pamakore makumi mashanu, chiitiko ichi chinonzi kuenda kumwedzi.

Muvanhu

Varume mageteti mune mamwe mazwi spermatozoa maseru enhare ayo anopfuura makumi matanhatu emakiromita (60 mm) akareba, ayo mashanu chete ma micrometer ari emusoro.

Urume uhu, hwakaumbwa kunge tadpole yedatya, hwakaumbwa nezvikamu zvitatu: musoro, chikamu chepakati nemuswe. Musoro wakaita sedenderedzwa une kosi iyo pachayo inogadzira ma chromosomes. Iwo ari makumi maviri nematatu echromosomes anonzi autosomes + 23 chromosome yakanangana nekodhi yekubata, ndiko kuti izvo zvinotara bonde remunhu, murume kana mukadzi.

Chikamu chepakati chine mitochondria uye zvinovaka muviri zvinobvumidza urume kutenderera. Pekupedzisira, urume hune muswe murefu, unonzi flagellum, uyo unoitendera kuti izvisumudze pachayo nenzira refu yechibereko chemukadzi kuitira kuti isvike pachivharo nekuisanganisa.

Muvarume, kugadzirwa kwembeu, inozivikanwa se spermatogenesis, inotanga pakuyaruka, panguva yekuyaruka uye inoenderera kusvika parufu rwavo. Iyo spermatogenesis kutenderera inotora avhareji yemazuva makumi matanhatu nemasere, saka zvinotora ingangoita mwedzi miviri nehafu kuti testis iite urume. Uye machende anoita kuti irambe ichienderera. Kunyangwe kugadzirwa kuri pasi pekusiyana, avhareji kugadzirwa kunoonekwa semamirioni zana urume pazuva.

Iwo ma testes anoburitsa urume, asiwo huturu hwemuviri hunogadzirwa nemaseminal vesicles neprostate. Musanganiswa uyu unoumba urume. Iyo inoumbwa ne90% inovaka mvura uye 10% urume.

Gametes maseru akasarudzika ane basa rekusimbisa kubereka. Kuti hurume huitike, chirume chinofanirwa kusangana nezai uye chisanganike nacho. Mbeu imwe chete inowanzo gamuchirwa nezai, iro rinovhara zvaro pachinongopinda munzira yevamwe.

Munguva yehukama hwepabonde, vanogona kubatana nemagame evakadzi vakasiyana uye mumwe obva ataura nezvekusangana, izvo zvingangoburitsa munhu mutsva.

Kune kuwanda kwezviitiko apo vese varume nevakadzi gameti vanogona kuratidza kusakanaka. Zvimwe mukugadzirwa kwavo, kusavapo kana kukwana spermatozoa, kana ova yekudyara. Urume hauna kusimba zvakakwana kuti usvike zai, richiisa zai panzvimbo isiri iyo.

Kune zvakare kusarongeka kwemajini, ayo anosanganisira kusagadzikana mune ramangwana kana chirwere chemagene, "ndizvo zvazvakaita naTrisomy 21. Kazhinji kacho" embryo "haiendeswe kunopera nemuviri wemukadzi anoona kusagadzikana.

Kuongororwa kunoitwa pamatanho akasiyana epamuviri kudzivirira njodzi yekusagadzikana kwemagene.

Chipo chaGamete chine chekuita nevaroorani vezera rekubereka vanofanirwa kutsvaga kubatsirwa nachiremba, kungave nekuti mumwe wevakaroora anorwara nekushaya mbereko, kana nekuti pane mukana wekutapurira chirwere chakakomba kumwana kana kune mumwe wevakaroora.

Kufanana nezvimwe zvese zvipo zvezvinhu uye zvigadzirwa zvemuviri wemunhu, kupihwa kwemagametes chiito chekubatana, chinotongwa nemisimboti mikuru yemutemo webioethics: kusazivikanwa, kusununguka uye kubvumirana.

Huwandu hwevaroorani vakamirira chipo chemagameti uye kushomeka kwemipiro chaiko chaizvo. Huwandu hwevaroorani vakanyoreswa pane akamirira mazita ezvivakwa nzvimbo zviri kuwedzera gore rega rega. Chirongwa chehushumiri che2017-2021 chekuita kubereka chinopa pekutanga kuvandudzwa kwemupiro we gamete kuenda kune hwenyika kuzvigutsa.