Video: Kev tshem tawm chromosome txhais li cas?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Hauv genetics, a kev tshem tawm (tseem hu ua gene kev tshem tawm , deficiency, los yog kev tshem tawm mutation) (kos npe: Δ) yog ib tug mutation (ib tug genetic aberration) nyob rau hauv uas ib feem ntawm a chromosome los yog ib ntu ntawm DNA yog sab laug thaum lub sij hawm DNA replication. Muaj pes tsawg tus nucleotides ua tau yuav deleted, los ntawm ib lub hauv paus mus rau tag nrho cov chromosome.
Tom qab ntawd, chromosome deletion ua rau dab tsi?
Chromosomal tshem tawm Syndromes tshwm sim los ntawm kev poob ntawm qhov chaw chromosomes . Lawv muaj peev xwm ua rau loj congenital anomalies thiab tseem ceeb kev txawj ntse thiab lub cev tsis taus. Chromosomal tshem tawm Syndromes feem ntau suav nrog loj dua kev tshem tawm , uas yog feem ntau pom ntawm karyotyping.
Kuj Paub, qhov kev tshem tawm chromosomal yog dab tsi? Lub sij hawm " kev tshem tawm " tsuas yog txhais tau tias yog ib feem ntawm a chromosome ploj lawm los yog "deleted." Ib qho me me ntawm a chromosome tuaj yeem muaj ntau cov noob sib txawv. Thaum cov noob ploj lawm, tej zaum yuav muaj qhov yuam kev hauv kev loj hlob ntawm tus menyuam, vim qee qhov "cov lus qhia" ploj lawm.
Ib yam li ntawd, yuav ua li cas thaum tshem tawm ntawm chromosome?
A kev tshem tawm kev hloov pauv tshwm sim thaum ib feem ntawm DNA molecule tsis tau theej thaum lub sij hawm DNA replication. Qhov tsis tau luam tawm no tuaj yeem ua me me li ib qho nucleotide lossis ntau npaum li tag nrho chromosome . Kev poob ntawm DNA no thaum rov ua dua tuaj yeem ua rau muaj kab mob caj ces. Hauv ib qho kev hloov pauv ib qho yuam kev tshwm sim hauv ib qho nucleotide.
Koj puas tuaj yeem muaj sia nyob nrog lub chromosome uas ploj lawm?
Yog tias lub cev muaj tsawg lossis ntau dhau chromosomes , feem ntau nws yuav tsis ciaj sia mus yug. Tsuas yog qhov twg a tsis muaj chromosome kev zam txim yog thaum X lossis Y chromosome yog ploj lawm . Tus mob no, hu ua Turner syndrome lossis XO, cuam tshuam txog 1 ntawm txhua 2,500 tus pojniam.
Pom zoo:
Nws txhais li cas hais tias peb txhua tus muaj qhov kev tawm tsam rau kev txawj ntse?
Hauv cov noob caj noob ces, cov tshuaj tiv thaiv kab mob (tseem hu ua ntau yam ntawm cov tshuaj tiv thaiv) yog thaum cov phenotype (cov yam ntxwv qhia) ntawm cov kab mob nyob ntawm ob qho tib si ntawm lub cev cov yam ntxwv ntawm caj ces (genotype) thiab ib puag ncig. Piv txwv li, ob tug nus muag tau tsa ua ke tuaj yeem muaj qhov sib txawv IQs thiab cov txuj ci ntuj
Dab tsi qib ntawm kev ywj pheej tshem tawm qhov kev txwv tangent?
Ib qho kev txwv tangent tshem tawm ib qib ntawm kev txhais lus tawm. Nyob nruab nrab ntawm lub tog raj kheej thiab lub dav hlau, nws tshem tawm ib qib ntawm kev ywj pheej ntawm kev ywj pheej thiab ib qib kev ywj pheej ntawm kev sib hloov. Sab hauv Cov Haujlwm Thawj qhov xaiv hauv qhov thib ob xaiv ntawm qhov tangent point
Koj yuav daws tau qhov system ntawm peb qhov sib npaug li cas los ntawm kev tshem tawm?
Xaiv ib qho sib txawv ntawm ob qhov sib npaug, hais qhov sib npaug (2) thiab (3), thiab tshem tawm qhov sib txawv. Kev daws qhov system tsim los ntawm kev sib npaug (4) thiab (5). Tam sim no, hloov z = 3 rau hauv kab zauv (4) kom pom y. Siv cov lus teb los ntawm Kauj Ruam 4 thiab hloov mus rau hauv ib qho kev sib npaug uas muaj qhov sib txawv ntxiv
Puas yog kev tshem tawm ib qho kev hloov pauv?
Kev rho tawm kev hloov pauv tshwm sim thaum ib feem ntawm DNA molecule tsis tau theej thaum lub sijhawm DNA rov ua dua. Hauv ib qho kev hloov pauv 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 cov ntsiab lus tshem tawm, ib qho nucleotide tau raug tshem tawm ntawm qhov sib lawv liag
Vim li cas kev ntxig thiab tshem tawm hu ua frameshift mutations?
Piav tias yog vim li cas kev ntxig thiab tshem tawm yog hu ua frameshift mutations siv cov ntsiab lus nyeem ncej, codons, thiab amino acids hauv koj cov lus teb. Lawv hu ua frameshift mutations vim qhov kev nyeem ntawv yog qhov tseem ceeb hloov. Qhov ua ntej ntawm qhov kev tshem tawm lossis kev tso tawm tshwm sim, qhov hloov pauv ntau ntawm cov protein