Ngenxa yokuthi umama nguye omzimba wakhe okhulelwe, izimbangela eziningi zokusola okuphathelene nezifo zihlobene nezimo ezikhona kumama. Kodwa njengoba izinkinga ze-chromosome ziyimbangela ehamba phambili yokukhulelwa kwesisu kanye nengxenye ye-chromosomes yokukhula kwengane ivela kubaba, ungase uzibuze ukuthi into ethile ku-sperm ingaba yisisusa sokukhulelwa kwesisu-ikakhulukazi uma uye wahlukunyezwa okuningi.
Ingabe Izinkinga Ngezimbangela Kungabangela Ukuhlukunyezwa?
Impendulo mhlawumbe. Esikhathini esidlule, abacwaningi baye bagxila eqanda njengendlela eyinhloko yezinkinga ze-chromosome ngezizathu eziningana. Esinye sezizathu ukuthi (ngokuvamile) iqanda elilodwa kuphela elivotelwe umjikelezo ngamunye wokuya esikhathini, kodwa ukhetho lwemvelo lwenzeka phakathi kwesidoda ngaphambi kokukhulelwa ukuthi ngokwemfundiso kufanele kuholele "ekugcineni" ukuthi yilokho okufanele kufinyelele iqanda. Ukwengeza, izifundo zofuzo ezivela emasongweni ahlukumezekile zilandele amaphutha esiteji sokuqala se-maternal meiosis (ukuthuthukiswa kokuqala kweqanda) njengokungathi kungumthombo wezinto ezingavamile ezibangelwa ukungaziphathi kahle.
Kodwa ucwaningo olwengeziwe kule minyaka eyishumi edlule luveza ukuthi lokhu kungase kungabi njalo njalo . Ezinye izimo zokuhlukunyezwa okuphindaphindiwe kubonakala sengathi zibandakanya ubaba onesisindo esiphakeme sama- chromosomes angavamile kumuntu wakhe. Azikho izilinganiso zangempela zokuthi i-sperm iyindlela engakanani emithanjeni ephindaphindiwe, futhi izinkinga ze-chromosome ku-sperm azikholelwa ukuthi ziyimbangela enkulu yokulahlekelwa okuphindayo, kodwa kubonakala sengathi kungenzeka-ikakhulukazi emadodeni insimu yabonisa i-morphological engavamile noma ezinye izimpawu zokuzala okuphansi.
Abanye odokotela bangase batuse ukuthi amadoda ahlolwe izinga lekhanda uma kungekho enye imbangela yezimo eziphuthumayo eziphindaphindiwe ezitholakala. Ikhwalithi yesipelingi ngezinye izikhathi, kodwa hhayi ngaso sonke isikhathi, ingathuthukiswa ngezinguquko zokuphila noma imithi.
Ukuqothula kokuqala kweThathu
Amaphutha angama-3 kwangu-4 avela phakathi nenyanga yokuqala yokukhulelwa.
Ngokujwayelekile, uma owesifazane enesisu ngesikhathi sokuqala, kwaba nenkinga ngama-chromosomes wengane. Ama-Chromosomes ayimabhuloki e-DNA equkethe i-encode yonke imininingwane edingekayo ngesikhathi sokuthuthukiswa.
Ngenkinga ye-chromosomal, into e-awry yenzeka ngesikhathi sokukhulelwa futhi umbungu uthola inombolo engafanele yama-chromosomes (amaningi kakhulu noma ambalwa kakhulu) ekugcineni avele ekukhulelweni kokukhipha isisu. Okuphawulayo, akuzona zonke izingane ezinenani elingalungile lama-chromosomes azikhishwa kabi. Isibonelo, izinsana ezine-trisomy 21 zine-Down's syndrome.
Ngezinye izikhathi, kwenzeka okuthile okuholela ekukhulelweni okungahambisani neze nama-chromosomes. Isibonelo, uma kunezinkinga nge-placenta, ingozi yokukhulelwa kwesisu iyakhula. Khumbula ukuthi umntwana udinga i-placenta ukuthola igazi lomama.
Nazi ezinye izimbangela zokukhulelwa kwesisu ngesikhathi sokuqala kwe-trimester:
- ukubhema
- ukukhuluphala
- ukusetshenziswa kwezidakamizwa ezingekho emthethweni
- ukusetshenziswa kotshwala
Ukuxoshwa Kwesibili Kwemithathu
Nakuba ukuhlukunyezwa okuningi kwenzeka ngesikhathi sokuqala kwe-trimester, ukuhlukumeza kwamaphutha nakho kwenzeka phakathi nenyanga yesibili.
Nazi ezinye izizathu zokuthi kungani ukukhulelwa kwesisu kwenzeka ngesikhathi se-trimester yesibili:
- isifo sikashukela
- isifo sezinso
- lupus
- izinkinga ze-hormone
- ukutheleleka
- ukudla okunobuthi obukhulu
- umlomo wesibeletho obuthakathaka
- fibroids
Sicela uqaphele ukuthi lezi zinto ziyizinto eziyingozi nje kuphela. Ngamanye amazwi, akuwona wonke owesifazane onesifo sikashukela oyobhekana nokukhulelwa kwesisu.
Ekugcineni, abantu abaningi abanesisu abasoze bazi kahle ukuthi kungani babe munye. Izici eziningana zifaka engozini yokukhulelwa kwesisu.
Imithombo:
Al-Hassan, S., A. Hellani, A. Shahrani, M. Al-Deery, K. Jaroudi1 no S. Coskun. "I-Sperm Chromosomal Engavamile Kuziguli Ezikhipha Isisu Esingajwayelekile." Biology Systems ngoMuthi Wokuzala 2005, Umq. 51, No. 1, Amakhasi 69-76.
Egozcue, S., J. Blanco, JM Vendrell, F. García, A. Veigad, B. Aran, PN Barri, F. Vidal noJegozcue. "Ukungasebenzi kwabantu besilisa: ukukhubazeka kwe-chromosome, ukuphazamiseka kwe-meiotic, i-spermatozoa engavamile nokukhipha isisu okuphindaphindiwe." Ukuvuselela Ukukhiqizwa Komuntu, Vol.6, No.1 kk. 9-10-10, 2000.
UHassold, uTerry, Heather Hall noPatricia Hunt. "Imvelaphi yomuntu aneuploidy: lapho siye saba khona, lapho siya khona." I-Human Molecular Genetics 2007 16 (R2): R203-R208; i-doi: 10.1093 / hmg / ddm243.
Sun, Fei, Evelyn Ko noRenee H. Martin. "Ingabe kukhona ubudlelwane obuphakathi kwe-sperm chromosome engavamile kanye ne-sperm morphology?" Biology Yokukhiqiza Ne-Endocrinology 2006, 4: 1iyi: 10.1186 / 1477-7827-4-1.
UZini, Armand, noJamie Libman. Umonakalo we-DNA: ukubaluleka komtholampilo ngesikhathi sokusiza ukukhiqiza. " I-CMAJ • Ngo-Agasti 29, 2006; 175 (5).