Ingabe Baklanywa?
Ubuhlobo Obumangalisayo Emhlabathini
◼ Emhlabathini kunobuhlobo obumangalisayo phakathi kwezitshalo ezithile nama-bacterium obusiza ukuba kube nokuphila.
Cabangela lokhu: I-nitrogen ibaluleke kakhulu ekukhuleni kwesihlahla nasekuvezeni izithombo zaso ezintsha. Kodwa igesi kufanele iguqulwe, noma ishintshwe, ibe yingxube njenge-ammonia ngaphambi kokuba isetshenziswe yimvelo. Izitshalo eziyimidumba zixazulula le nkinga ngokubambisana nama-bacterium abizwa ngokuthi ama-rhizobia. Ubuhlobo obunjalo bokusizana obuphakathi kwalezi zinto ezingafani bubizwa ngokuthi i-symbiosis.
Ngosizo lwekhemikhali ethile, imidumba idonsela ama-bacterium ezimpandeni zayo, bese engena ngaphakathi kwazo. Umagazini i-Natural History uthi nakuba ama-bacterium nesitshalo kungamalungu emikhakha emibili ehlukene, kuyasebenzelana “ukuze kwakhe ingxenye entsha ngokuphelele: iqhuzwana lezimpande eziguqula i-nitrogen ngokuphelele.” Phakathi kwaleli qhuzwana, ikhaya lawo elisha nendawo yokusebenza, ama-bacterium aqala ukusebenza. Ithuluzi lawo eliyinhloko uhlobo olukhethekile lwe-enzyme—uhlobo oluthile lweprotheni olubizwa ngokuthi i-nitrogenase—alusebenzisela ukuguqula i-nitrogen engena ngezimbobo emhlabathini.
Umagazini i-Natural History uthi: “I-nitrogenase ekuwo wonke umhlaba . . . inganela ebhakedeni elilodwa elikhulu.” Ngakho wonke amangqamuzana abalulekile! Kodwa kunenkinga ethile. Le-enzyme yonakaliswa umoya-mpilo. Siyini isisombululo? Umdumba ukhiqiza isakhi esithile esikhethekile esikhipha umoya-mpilo ongase ube ingozi.
Ulwelwesi oluzungeze leli qhuzwana lulawula ukushintsha kwe-ammonia, ushukela, nezinye izinhlobo zezakhi phakathi kwama-bacterium nesitshalo. Njengazo zonke izitshalo imidumba ekugcineni iyafa. Lapho lokhu kwenzeka, i-ammonia isala enhlabathini. Ngakho-ke, imidumba iye yabizwa ngokufanele ngokuthi “umquba oluhlaza.”
Ucabangani? Ingabe ama-bacterium nezitshalo asebenzelana nazo “asungula” le nkimbinkimbi yesimiso sokuphila esimangalisayo, noma ingabe sinobunye futhi ubufakazi bomklamo?
[Isithombe ekhasini 25]
Iqhuzwana lempande
[Imithombo Yesithombe ekhasini 25]
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