I-oocyte yileqanda elidala (i-ovum edala). I-Oocytes ikhula ibe yintshumayelo ukusuka ngaphakathi kwintolthi . Ezi follicle zifumaneka kwinqanaba langaphandle. Ngexesha lomjikelezo ngamnye wokuzala , iifolli eziliqela ziqala ukuphuhlisa.
Ngokuqhelekileyo, i-oocyte enye yodwa umjikelezo uya kuba liqanda elivuthiweyo kwaye ikhutshwe kwi-follicle yayo. Le nkqubo iyaziwa njenge- ovulation .
Ibhinqa izalwe nazo zonke ii-oocytes eziza kuba nazo. Le nani inciphisa ngokwemvelo ngokweminyaka . Ubudala buyanciphisa umgangatho kunye nokuzinza kwezofuzo ze-oocytes. Yingakho kunzima ukukhulelwa emva kwama-35 .
I-ovum ekhulile ebonakalayo iliso lomntu, lilinganisa i-0.1 mm. Yimalunga nobukhulu bexesha ekupheleni kwesi sigwebo.
Ukusetyenziswa kweziyobisi kunokunyusa inani lokuphucula ii-oocytes kunye nokugqithisa njengamaqanda aqolileyo. Esi sizathu sengozi ephezulu yokukhulelwa ngokuphindaphindiweyo xa kuthatha iziyobisi. Kuwo wonke ovum ovulated, kukho inokwenzeka ukuba inokukhutshwa ngumzimba wesinambu. Le ova ekhulelweyo ingaba yimibungu (kwaye, ekugqibeleni, ukuba zonke ziyahamba kakuhle, iintsana.)
Ngexesha lokunyanga , ugqirha uya kuqhuba i-ultrasound ukujonga ukukhula kobugqwetha. Ukuvuthwa kwe-oocyte kuya kwenzeka, kodwa ukuvuthwa kwe-oocyte akubonakali kwi-ultrasound. Yingakho ukukhula kobugqirha kubonwa kwaye akukho ukukhula kwe-oocyte.
Ukuba iifolli ezininzi zikhula, umjikelo wakho wonyango unokukhanselwa ukukhusela umngcipheko wokukhulelwa okuphindaphindiweyo okanye i- ovarian hyperstimulation syndrome (OHSS) .
Ngexesha le- IVF , ukuba iliso lokujonga i-ultrasound alubonakali ngokwaneleyo ukukhula kwe-follicle-oku kuthetha ukuba akukho i-oocytes eyaneleyo yokukhula-umjikelo unokucinywa ukuba ukhuphe ukuphulwa kweyeza.
Ezinye iindlela zokupasa: i-oöcyte, i-ovocyte, i-ocyte.
Izigaba ze-Oocyte
I-Oogenesis yintoni i-oocyte ehamba ngayo njengoko ikhula kwi-ovum ekhulile.
Unokucinga ukuba i-oogenesis iqhutywe ngaphaya kweenyanga ukusuka ekubeni yindlela edla ngayo. Kodwa uya kuphosakela!
Nangona kuyi nyaniso ukuba nayiphi na iqanda eligqityiweyo lizalisa inkqubo ye-oogenesis inyanga ikhutshwa kwi-ovary, i-oocyte yophuhliso yaqala indlela ngaphambi kokuba uzalwe.
Enyanisweni, yaqala xa wawusemncinci kakhulu.
Ezi zezigaba zokukhula kwe-oocyte.
KwiSiginal Cell Cell
Inxalenye "yembewu" nganye ye-oocyte yile ntsho yegciwane lesigulo.
Lawa maseli e-embryonic ekugqibeleni abe yimizimba yesininzi okanye i-oocyte.
Kwi-embryo ekhulayo, la maseli ahamba kwindawo leyo ekugqibeleni iya kuba yi-testis okanye i-ovari (eyaziwa ngokuba yi-gonads).
Inqaku elichaphazelekayo: Uphando lufumene ukuba amanye ala maseli e-oocyte asekuqaleni akhona kuma-ovari esetyhini. zikhawulelwe kumaqanda awazalelwe nawo.)
Oogonium
Emva kokuba i-gelads ye-germ ehamba phambili ifikelele kwi-gonads, ithonyelwa ngamaseli azungeze ukuba yi- oogonium .
(Okanye, ngobuninzi, i- oogonia .)
I-Oogonia iiseli ze-diploid . Oku kuthetha ukuba babini (di) bazalise iiseti ze-chromosomes. Kwiseli yomntu, le mibini engama-23 okanye i-46.
Oku kuyinto ebalulekileyo ukwazi ukuba i-oocyte ekugqibeleni iya kuba nehafu okanye ama-chromosomes angama-23. (Ngexesha lokuchumisa, liza kufumana elinye i-23 kwisalathini yesilisa ukuba ibe nesicwangciso esipheleleyo kwakhona.)
Ngexesha leenyanga ezintlanu zokuphuhliswa kokubeletha, ukunyuka kwe-oogonium kwinombolo ngokusebenzisa inkqubo eyaziwa ngokuba yi- mitotic cell division .
I-Meiosis ihlukile kwiiseli zentsholongwane. Kuphela kuphela kwiiqanda ezincinci kunye namaselingi esilisa.
Ngokwahlulo oluthile lweeseli-olubizwa ngokuba yi-meiosis-iiseli eziphindaphindiweyo ngokwenza ama-clones, nganye isineti epheleleyo ye-chromosomes.
Ngokomzekelo, iseli elilodwa lesikhumba elihamba nge-mitosis ekugqibeleni liza kubakho kwiiseli ezimbini zesikhumba, kunye neendlela ezifanayo zofuzo.
Ngethuba lokwahlukana kweeselilo ze-cell, i-oogonium iyahlukana kwiiseli ezimbini ezihlukeneyo eziqulethe:
- Isiqingatha se-chromosomal isethi: ngamanye amagama, anama-chromosomes angama-23 kuphela. (Ezi zibizwa ngokuba ngama-haploid cells.)
- Iisethi ze-chromosomal eziyingqayizivele: zonke i-oogonium ezahlukanayo zenza amaseli oodade ahlukile. Oku kuthetha ukuba akukho mntu oogonium onokwabelana ngendlela efanayo ye-chromosomal.
Ulwahlulo lwama-mitotic kutheni yonke into entsha yobomi inokwenziwa kwezinto eziphilayo ezahlukileyo ezingafani nomnye umntu.
Nangona kunjalo, akuyiyo yonke indawo. Yonke isekelwe kwimpahla yokuzalwa ye-gene embryo efunyenwe kubaba nonina.
Ezi iiseli ziyaqhubeka ziphindaphinda zize zifikelele kwinqanaba. Ingqungquthela eyenzekayo xa umntwana okhulayo ehamba ngeenyanga ezintlanu.
Kule nkalo, intombazana yentombazana ine-oocytes yezigidi ezi-7.
Le nani iya kuqala ukuhla emva kweli nqaku. Ekuzalweni, intombazana isana ne-oocytes yezigidi ezi-2 kuphela.
Oocytes Primary
Yonke i-oocyte iya kuhamba ngeesahlulo ezimbini zee-cell i-meiotic ngaphambi kokuba ibe yi-ovum ekhulile. Ulwahlulo lwamaseli e-Meiotic lukhokelela ekukhuleni nasekukhuleni kwe-oocyte, kungekhona ii-oocytes ezongezelelweyo.
Ngasekupheleni kokuphuhliswa kokubeletha, ii-oocytes ziyeka ukuphindaphinda kwinani kwaye ziqale ukukhula ngokwabo.
Kule nqanaba, bahamba ngeqela lokuqala lokwahlukana kweeselitic. Ukwahlukana kweeseli kukhokelela ekukhuleni kwe-oocyte-engekho i-oocyte-njengento eyenzekayo nge-oogonium.
Kodwa abahambi nje ngokukhawuleza ekuphuhliseni ukukhula ngokwangoku.
Ii-oocytes eziphambili zikhupha ekuphuhlisweni kwazo kwaye zihlala zityinwe de kubekho i-hormone yokuzalisa inqanaba elilandelayo.
U-Oogenesis uya kuqhubeka ngexesha lokufikisa.
I-Oocyte yesiSekondari
Ukunyuka kwamathuba omntwana-uqala ukuqala kwinqanaba elilandelayo lokukhula kwe-oocyte.
Akunjalo onke ama-oocyte aya kuhamba kwezi zigaba ezilandelayo zokuphuhliswa kwe-oocyte kunye, kunjalo. Baninzi baphambuke kwixesha lokuzala. Ngenyanga nganye, i-oocyte eyimfuneko yokuqala iqala ukukhula.
Xa i-oocyte eyinhloko ichaphazeleka ngamahomoni azalisayo, izalise iSigaba I sohlulo lweseli ye-meiotic. Oku kuyaziwa ngokuba yi- oocyte maturation .
Ekupheleni kwesi sigaba sokuqala sokuhlukana kweeselitic cell, iseli lidibanisa kwiiseli ezimbini ezihlukeneyo: umzimba omncinci we-polar kunye ne-oocyte enkulu yesibini.
Umzimba omncinci we-polar ugqityiwe ekugqibeleni.
I-oocyte yesibini iqalisa isigaba esilandelayo sokukhula.
Ootid
I-oocyte ngoku iqalisa isigaba sesibini seqela le-meiotic division.
Ekugqibeleni, i-oocyte yesibini iya kuphinda ihlulwe kwakhona kwiiseli ezimbini ezihlukeneyo: enye inqwelana encinane yomzimba kunye neseli ekhulile.
Le seli ekhulile ekhulile iyaziwa njenge-ootid.
Njengaphambili, inqununu yomzimba we-polar ekugqibeleni iya kulahla.
Ukuvuthwa kwenzeka xa i-oocyte ifinyelele kwisigaba se-ootid sophuhliso.
Ovum
Ngethuba le-ovulation, i-ootid ikhutshwa kwi-follicle.
Iisetyhi zeqanda lomntu azikwazi ukuhamba zodwa. Esikhundleni saloo ndlela, imijondolo efana neminwe ibonisa i-oocyte ukuya kwi-tube fallopian .
Xa sele ungaphakathi kwiphubhu ye-fallopian, iinwele ezincinci-ezinjengeziqendu ezibizwa ngokuba yi-cilia ziyaqhubeka zidweba i-ootid.
Kwi-tube fallopian, ukuba ukhulelwe, i-ootid ixutywa yi-cell cell.
Emva kokuba le mboleko iqhutywe, i-ootid ihamba kwisigaba sayo sokugqibela sokukhula komzimba kwaye iba yintambo ye-ovum, iseli elinoqili lomntu elivuthiwe.
Ilungile lo nto; i-oocyte ayikwazi ukuzalisa uphuhliso lwayo ngaphandle kokuchumisa.
Ukusuka kwi-Oocyte ukuya kwi-Ovum ukuya eZygote
Ngethuba lokuchumisa, i-ovum kunye ne-sperm cell cell, nganye iqukethe i-chromosomes ezingama-23 nganye.
Kunoko ngokukhawuleza (kodwa kungekhona ngexesha elichanekileyo lokuchumisa), la ma-chromosomes ahlangene kunye, ukudala iseli elitsha kunye neqoqo elipheleleyo lama-chromosomes.
Le seli elitsha libizwa ngokuba yi-zygote .
I-zygote iya kukhula ibe yimbungu kwaye, malunga neenyanga ezithoba, umntwana osandula.
Imithombo:
Alberts B, Johnson A, Lewis J, et al. Biology Biology yeSeli. 4 edition. ENew York: i-Garland Science; 2002. http://www.ncbi.nlm.nih.gov/books/NBK26842/
UGrudzinskas, uJurgis Gedimina; Yovich, JL Gametes - I-Oocyte . Iingxelo zeCambridge ekuzalweni kwabantu. I-edition 1, ngo-1995. Amaphepha 9 ukuya ku-10.
I-White YA1, i-Woods DC, iTakai Y, Ishihara O, uSeki H, uTilly JL. "Ukwakhiwa kwe-oocyte ngama-germ cells asetshenziselwa ukuguqula i-germs ehlanjululwe kwii-ovari zowesetyhini." UNathan Med. 2012 Feb 26; 18 (3): 413-21. i-doi: 10.1038 / nm.2669. http://www.nature.com/nm/journal/v18/n3/full/nm.2669.html