Video: Puas yog kev tshem tawm ib qho kev hloov pauv?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
A kev hloov pauv tshwm sim thaum ib feem ntawm DNA molecule tsis tau theej thaum lub sij hawm DNA replication. Hauv ib point kev hloov ib qho yuam kev tshwm sim hauv ib qho nucleotide. Tag nrho lub hauv paus khub yuav ploj, lossis tsuas yog lub hauv paus nitrogenous ntawm tus tswv strand. Rau taw tes tshem tawm , ib tug nucleotide tau ua tshem tawm los ntawm cov kab ke.
Tsis tas li ntawd, dab tsi yog qhov kev hloov pauv deletion?
Hauv genetics, a kev tshem tawm (tseem hu ua gene kev tshem tawm , deficiency, los yog kev hloov pauv ) (cim: Δ) yog a kev hloov pauv (ib tug genetic aberration) nyob rau hauv uas ib feem ntawm ib tug chromosome los yog ib theem zuj zus ntawm DNA yog tso tawm thaum lub sij hawm DNA replication. Txhua tus lej ntawm nucleotides tuaj yeem raug tshem tawm, los ntawm ib lub hauv paus mus rau tag nrho cov chromosome.
Ib sab saum toj no, dab tsi yog 3 hom kev hloov pauv ntawm cov ntsiab lus? Muaj peb hom DNA Mutations: lub hauv paus hloov, tshem tawm thiab ntxig.
- Kev hloov pauv hauv paus. Ib qho kev hloov pauv yog hu ua point mutations, nco qab qhov kev hloov pauv ntawm Glu --- Val uas ua rau mob qog nqaij hlav.
- Kev tshem tawm.
- Insertions.
Ib yam li ntawd, nws raug nug, puas yuav tag nrho kev ntxig lossis tshem tawm kev hloov pauv?
Yuav tag nrho insertion lossis deletion mutations ua rau kev hloov pauv ntawm cov amino acid ib ntus? Yog vim muaj cov nucleotide tshiab uas yog ntxig / deleted hloov cov nucleotides, hloov cov ntawv ntawm ntau codons.
Puas yog frameshift mutation A point mutation?
Hauv ib point kev hloov , ib nucleotide yog swapped tawm rau lwm tus. Frameshift kev hloov pauv yog vim yog kev ntxig lossis tshem tawm ntawm nucleotides. Qhov no ua rau tag nrho DNA strand kom elongate los yog kom me me. Yog li, frameshift kev hloov tuaj yeem hloov tag nrho cov codons uas tshwm sim tom qab tshem tawm lossis tso.
Pom zoo:
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