Mhlawumbi, enye yemimangaliso emikhulu kwihlabathi kukuzalwa kobomi obutsha. Izidalwa ezimbini eziphilayo zidibanisa kwinkqubo yokuchumisa, ukwenzela ukuba iqhube i-genus yayo kwaye inike iindlalifa iimpawu zabo ezilungileyo. Kungenxa yokuba zonke izinto eziphilayo emhlabeni wethu zizama. Makhe sikhulume kweli nqaku malunga nokuba ukuchumisa kweqanda kwenzeka ntoni.
Kuphi ukuchumisa kwenzeka kubantu?
Lo mzuzu omangalisayo xa i-ovum kunye ne-spermatozoon iba enye, imfihlo encinane. Ukufakela umquba kubantu kubonakala kwiphubhu yomama, apho i-spermatozoa ihamba ngeendlela ezahlukeneyo. Iiseli zamadoda kufuneka zihambe ngendlela enzima, apho i-1% yazo kuphela iza kusinda, kodwa ziya kuba ngabameli abanobuchule, bephethe iimpawu ezingcono kumntwana ozayo. Abaninzi abasindileyo abaye bafikelela endaweni apho ukuchumisa kwenzeka khona kufuneka banqobe ukukhuselwa kweqanda, kwaye umntu omnye onenhlanhla uya kuphumelela. Ngokomthetho wendalo, i-strongestest isaphila apha.
Ukuzalwa ubomi obutsha
I-tube fallopian ithola kwi-ovari kuphela i-ovule ngexesha elithile. Isisele kufuneka sisayidlule enye yee-tublopian tubes. Uhlobo lulungiselela yonke into ngendlela yokuba kwinqanaba ngalinye lokuvela komntu omtsha ukhetha ukunika umntwana kuphela. Ukufikelela kwiintsuku ezintlanu, uhambo lobomi bexesha elizayo luya kuhlala lude lu fi kelele apho indawo yokuchumisa kwenzeka khona. Nanku kuphela kuphela i-spermatozoon engena kwinucleus yeqanda, kunye kunye yakha i-zygote-encinci kodwa eyona nto ibalulekileyo iseli yokuqala, imakalisa ukubonakala komntwana. Ngokuqinisekileyo, eli selula lifumana ngokutsha ukhuseleko olutsha, luqine ngaphezu kwegobolondo yangaphambili, ukuba lukhuphe ngokupheleleyo ukuba lunokuchaphazela ezinye iiseli zesilisa kwi-zygote.