Duba wurin da ke ƙasa sannan ka amsa tambayar daga baya a cikin harshe ɗaya kamar yadda wurin yake:  Passage: Juyin halitta a cikin kwayoyin halitta yana faruwa ta hanyar canje-canje a cikin halaye na gado - halayen da aka gada na kwayoyin halitta. A cikin mutane, alal misali, launin ido shine halayyar da aka gada kuma mutum zai iya gadon "halayyar launin ruwan kasa" daga ɗayan iyayensu. Abubuwan da aka gada suna sarrafawa ta hanyar kwayoyin halitta kuma ana kiran cikakkun kwayoyin halitta a cikin kwayoyin halittar kwayoyin halitta (kayan halittar kwayoyin halitta). Ana kiran cikakkun halaye na halayen da aka lura da su wanda ke samar da tsari da halayyar kwayoyin halitta da phenotype. Wadannan halaye sun fito ne daga hulɗar genotype tare da yanayin. A sakamakon haka, yawancin bangarorin phenotype na kwayoyin halitta ba a gado ba. Alal misali, fatar da aka yi da rana ta fito ne daga hulɗar da ke tsakanin nau'in halittar mutum da hasken rana; saboda haka, ba a ba da sunadarai ga 'ya'yan mutane ba. Koyaya, wasu mutane suna saurin tan fiye da wasu, saboda bambance-bambance a cikin bambancin genotypic; misali mai ban mamaki shine mutanen da ke da halayen gado na albinism, waɗanda ba sa tan da gaske kuma suna da matukar damuwa da ƙonewar rana. Ana ba da halayen gado daga tsara zuwa tsara ta hanyar DNA, kwayar da ke ɓoye bayanan kwayoyin halitta. DNA wani dogon biopolymer ne wanda ya kunshi nau'ikan tushe guda huɗu. Jerin tushe tare da takamaiman kwayar DNA yana ƙayyade bayanin kwayar halitta, ta hanyar da ta yi kama da jerin haruffa da ke furta jumla. Kafin tantanin halitta ya rabu, ana yin kwafin DNA, saboda haka kowanne cikin tantanin biyu da aka samu zai gaji jerin DNA. Sassan kwayoyin DNA da ke ƙayyade ɗayan aiki guda ɗaya ana kiransu kwayoyin halitta; kwayoyin halitta daban-daban suna da jerin daban-daban na tushe. A cikin ƙwayoyin halitta, dogon DNA yana ƙunshe da abubuwa da ake kira chromosomes. An san takamaiman wuri na jerin DNA a cikin chromosome a matsayin wuri. Idan jerin DNA a wurin ya bambanta tsakanin mutane, ana kiran siffofin daban-daban na wannan jerin allele. Tsarin DNA na iya canzawa ta hanyar maye gurbi, samar da sababbin allele. Idan juyin halitta ya faru a cikin kwayar halitta, sabon allele na iya shafar halayyar da...  Tambaya: Yaushe ake yin kwafin DNA dangane da rarraba sel?
Kafin tantanin halitta ya rabu