I-DNA: i-molecule eyashintsha i-biology
Uhambo Lokutholwa Kwempilo
Ukutholakala kwesakhiwo se DNA simi njengesinye sezikhathi ezibaluleke kakhulu emlandweni wesayensi, okuphawula ukuqala kwenkathi entsha ekuqondeni ukuphila ezingeni lamangqamuzana. Ngenkathi uJames Watson futhi UFrancis Crick ngokuvamile kuthiwa yi-double helix structure ye-DNA ngo-1953, kubalulekile ukuqaphela igalelo eliyisisekelo URosalind Elsie Franklin, ucwaningo lwakhe olwalubalulekile kulokhu kutholwa.
U-Rosalind Elsie Franklin: Iphayona Elikhohliwe
URosalind Franklin, usosayensi waseBrithani ohlakaniphile, wadlala indima ebalulekile ekuqondeni ukwakheka kwe-DNA ngomsebenzi wakhe wokuphayona I-X-ray crystallography. UFranklin wathola izithombe ezinemininingwane ye-DNA, ikakhulukazi edumile Isithombe 51, okwembula ngokucacile i umumo we-helix kabili. Kodwa-ke, iqhaza lakhe alizange lamukelwe ngokugcwele ngesikhathi sokuphila kwakhe, futhi kamuva nje umphakathi wesayensi waqala ukugubha indima yakhe ebalulekile kulokhu kutholakala okuyisisekelo.
Isakhiwo se-DNA: Ikhodi Yokuphila
DNA, noma i-deoxyribonucleic acid, iyi-molecule eyinkimbinkimbi equkethe i- iziqondiso zofuzo eziyisisekelo okudingekayo ekuthuthukisweni, ekusebenzeni, nasekuzalweni kabusha kwazo zonke izinto eziphilayo namagciwane amaningi. Isakhiwo sawo singese-double helix, eyatholwa uJames Watson, uFrancis Crick, futhi, ngenxa yeminikelo eyisisekelo kaRosalind Franklin, isibe olunye lwezimpawu ezibonakala kakhulu kwezesayensi.
Lesi sakhiwo se-helix esiphindwe kabili siqukethe imicu emibili emide amanxeba azungezile, afana nezitebhisi ezizungezayo. Isinyathelo ngasinye sezitebhisi sakhiwe ngamapheya ezisekelo ezinenitrogen, ezihlanganiswe ndawonye ngamabhondi e-hydrogen. Izisekelo ze-nitrogen i-adenine (A), i-thymine (T), i-cytosine (C), futhi i-guanine (G), futhi ukulandelana ezenzeka ngakho eduze komucu we-DNA kwakha ikhodi yofuzo yento ephilayo.
Imicu ye-DNA yakhiwe ushukela (deoxyribose) kanye amaqembu e-phosphate, nezisekelo ezine-nitrogen ezisuka kushukela njengezinqenqema zesitebhisi. Lesi sakhiwo sivumela i-DNA ukuthi iphindaphinde futhi idlulisele imininingwane yofuzo isuka kwelinye ingqamuzana iye kwelinye futhi isuka kwesinye isizukulwane iye kwesinye. Ngesikhathi sokuphindaphinda kwe-DNA, i-helix ephindwe kabili iyaqaqa, futhi umucu ngamunye usebenza njengesifanekiso sokuhlanganiswa kwentambo entsha ehambisanayo, iqinisekisa ukuthi ingqamuzana ngalinye lendodakazi lithola ikhophi elinembile le-DNA.
Ukulandelana kwezisekelo ku-DNA kunquma ukuhleleka kwama-amino acid kumaprotheni, okungama-molecule enza imisebenzi ebaluleke kakhulu kumaseli. Ngenqubo yokubhala, ulwazi lofuzo oluqukethwe ku-DNA lukopishelwa kulo isithunywa i-RNA (mRNA), ebese ihunyushwa ibe amaprotheni kuma-ribosomes eseli, kulandela ikhodi yofuzo.
Umthelela Wokutholwa Kwesayensi Yesimanje
Ukutholakala kwe-double helix structure se-DNA kuvule indlela yentuthuko yenguquko emkhakheni we biology yamangqamuzana, izakhi zofuzo, nemithi. Inikeze isisekelo sokuqonda ukuthi ulwazi lwezakhi zofuzo ludluliselwa kanjani ngokofuzo nokuthi uguquko oluholela ezifweni lungenzeka kanjani. Lolu lwazi luye lwagqugquzela ukuthuthukiswa kwamasu amasha okuxilonga, izindlela zokwelapha, ngisho ukuguqulwa kofuzo, eguqula kakhulu imithi kanye ne-biotechnology.
Ngale Kokutholakala: Ifa Locwaningo Oluhlanganyelwe
Indaba yokutholwa kwe-DNA iyisikhumbuzo se uhlobo lokusebenzisana lwesayensi, lapho yonke iminikelo, kungakhathaliseki ukuthi ibekwe obala noma cha, idlala indima ebalulekile ekuthuthukisweni kolwazi lomuntu. U-Rosalind Franklin, ngokuzikhandla kwakhe nokusebenza ngokucophelela, ushiye ifa elihlala njalo elidlula ukuqashelwa kwakhe kokuqala. Namuhla, indaba yakhe ikhuthaza izizukulwane ezintsha zososayensi, igcizelela ukubaluleka kobuqotho, uthando, kanye nokuqashelwa okufanele emkhakheni wesayensi.
Sengiphetha, ukutholakala kwesakhiwo se-DNA kuwumsebenzi wobungcweti wokusebenzisana kanye nobuhlakani bomuntu ngamunye, noWatson, uCrick, futhi ikakhulukazi uFranklin, bendawonye bembula izimfihlo ze-molecule yokuphila. Ifa labo liyaqhubeka nokuba nomthelela kwisayensi, okuvula amathuba angapheli ekusasa locwaningo lwezakhi zofuzo kanye nemithi.
Imithombo