Musoro: Mibvunzo yemuenzaniso uye Kukurukurirana kweMonohybrid Crosses
Pendauluan
Genetics ibazi rebiology rinoongorora kuti hunhu hunopfuudzwa sei kubva kune chimwe chizvarwa kuenda kune chinotevera. Imwe pfungwa huru mumagenetics imonohybrid cross, inova muchinjikwa une hunhu hwakasiyana hunosanganisira hunhu hwakasiyana. Zvese zvinonakidza uye zvinonetsa, monohybrid crosses zvinowanzo shandiswa kudzidza kuti maallele (marudzi ejini) anoshanda sei kuti aone hunhu hwechisikwa. Muchinyorwa chino, tichakurukura mienzaniso yakati wandei yezvinetso uye hurukuro yavo maererano nemonohybrid crosses.
Muenzaniso Mubvunzo 1: Kuyambuka Chirimwa Chembe
Muenzaniso wekare wemhando ye monohybrid crossing ndeye ongororo yaGregor Mendel nemiti yepizi. Mune imwe ongororo, Mendel akasanganisa chirimwa chepizi chine maruva epepuru (UU) nechirimwa chepizi chine maruva machena (uu).
Mubvunzo: Ndezvipi zviratidzo uye majini evana veF1 neF2?
Kukurukurirana:
- Chizvarwa cheF1:
Mendel akasanganisa chirimwa chine maruva epepuru (UU) nechirimwa chine maruva machena (uu). Nekuda kwekubatana uku, vana vese veF1 vachave ne genotype (Uu) nekuti vakawana allele imwe chete inotonga kubva kumubereki ane maruva epepuru uye allele imwe inodzokera kumashure kubva kumubereki ane maruva machena. Nekuti allele yepepuru (U) ndiyo inotonga, zvirimwa zvese zveF1 zvichave ne phenotype yepepuru. Saka, muchizvarwa cheF1, zvirimwa zvese zvine phenotype yepepuru ine heterozygous genotype (Uu).
- Chizvarwa cheF2:
Kana zvirimwa zveF1 (Uu) zvabatanidzwa, vana veF2 vanobuda vane huwandu hwe phenotypic hwe3:1, zvichibva paPunnett square. Kugoverwa kwe genotypic kunoitika i1 UU : 2 Uu : 1 uu. Kana tichitarisa phenotype, zvirimwa zvitatu zvichave nemaruva epepuru uye chimwe chichave nemaruva machena.
Saka, genotype yeF2 ine:
– 25% UU (homozygous inotonga)
– 50% Uu (heterozygous)
– 25% uu (homozygous recessive)
Mhando iyi inosanganisira:
– 75% maruva epepuru (UU neUu)
– 25% maruva machena (uu)
Muenzaniso Mubvunzo 2: Kuyambuka Mhuka
Funga nezvemuchinjikwa uri mumakonzo. Ngatitii allele yemvere nhema (B) ndiyo inotonga pamusoro peallele yemvere dzebrown (b). Kana mbeva ine heterozygous (Bb) ikasanganiswa nembeva ine homozygous recessive (bb), chii chichava phenotype uye genotype yevana vavo?
Kukurukurirana:
– Mbeva yekutanga ine hutachiona hwakasiyana-siyana (heterozygous) ine genotype (Bb), uye mbeva yechipiri ine hutachiona hwakasiyana-siyana (recessive homozygous) ine genotype (bb).
– Tichishandisa chikwere chePunnett, tinogona kuona musanganiswa weallele wevana:
| | B | b |
|—|—-|—-|
| b | Bb | bb |
| b | Bb | bb |
– Mhando dzemajini dzinobvira dzevana ndeidzi:
– 50% Bb (heterozygous)
– 50% bb (homozygous recessive)
- Panyaya ye phenotype:
– 50% yevana vachava nemvere nhema (Bb)
- 50% vachave nemvere dzebrown (bb)
Muenzaniso Mubvunzo 3: Kuberekesa mhuka dzakasiyana-siyana muvanhu
Muvanhu, ngatitii allele yeminwe yakajairika (N) ndiyo inotonga allele yeminwe yakawanda (n). Kana mumwe mubereki ari heterozygous nekuda kwehunhu uhwu uye mumwe mubereki ari homozygous nekuda kwe recessive, chii chinonzi phenotype-to-genotype ratio yemwana?
Kukurukurirana:
– Vabereki vane hutachiona hweHeterozygous vane genotype (Nn), uye vabereki vane hutachiona hwehomozygous vane recessive homozygous (nn).
- Tichishandisa maPunnett squares, tinowana:
| | N | n |
|—|—-|—-|
| n | Nn | nn |
| n | Nn | nn |
– Rudzi rwevana nderwekuti:
– 50% Nn (heterozygous)
– 50% nn (homozygous recessive)
– Mhando yemwana ndeiyi:
– 50% minwe yakajairika (Nn)
- 50% polydactyly (nn)
Mhedziso:
Kuyambuka kwemhando yemonohybrid chishandiso chakakosha mukunzwisisa misimboti yenhaka. Tichishandisa misimboti yekutanga senge kutonga uye kudzika kwenzvimbo, tinogona kufanotaura kupararira kwephenotypes uye genotypes muzvizvarwa zvinotevera. Chinhu chikuru chekunzwisisa kuyambuka kwemhando yemonohybrid kuziva zviratidzo zvealleles dzinotonga nedzinodzika uye kukwanisa kuvaka nekuongorora maPunnett squares. Kugara tichidzidzira nemuenzaniso wakasiyana-siyana kuchasimbisa ruzivo rwedu rwemajini ekutanga uye kuwedzera kunzwisisa kwedu kuti hunhu hunogarwa nhaka sei.
