Chikamu cheChromosome: Kunzwisisa Maumbirwo eMajini uye Basa rawo
Machromosome maumbirwo akaomarara anowanikwa mukati menucleus yemasero eukaryotic. Ane ruzivo rwemajini muchimiro cheDNA nemapuroteni, achiita basa rakakosha mukutapurirana kwehunhu kubva kuchizvarwa kuenda kune chimwe. Kuti unzwisise mashandiro emachromosome, zvakakosha kuti unyatsoongorora zvikamu zvawo uye kuti zvinobatsira sei pakushanda kwemajini. Muchinyorwa chino, tichaongorora zvikamu zvikuru zvemachromosome, zvinosanganisira centromeres, telomeres, chromatids, nezvimwe, uye mabasa azvo.
Chimiro Chekutanga cheChromosomes
Machromosome anoumbwa neDNA yakamonerwa zvakasimba yakakomberedza mamorekuru eprotein anonzi histones, zvichigadzira chimiro chinozivikanwa sechromatin. Mumasero eukaryotic, machromosome anoonekwa uye anorongwa panguva yekupatsanurwa kwemasero, mitosis uye meiosis. Chromatin yakamonerwa inoumba machromatids, ayo anotaridzika seshinda dzakamonerwa, uye chromosome yega yega ine machromatids maviri akafanana anonzi machromatids ehanzvadzi.
Centromere
Chimwe chezvinhu zvakakosha zvechromosome icentromere. Centromere chikamu chechromosome chinoshanda senzvimbo yekunamatira ma chromatids maviri uye ndiyo nzvimbo yekubatanidza kinetochore. Kinetochore chimiro cheprotein chakaoma chinonamatira ma spindle fibers panguva yekupatsanurwa kwemasero, zvichibatsira mukupatsanurwa kwakakodzera kwema chromatids kuita masero emwanasikana.
Centromere haisi nguva dzose iri pakati pechromosome; nzvimbo yayo inogona kusiyana. Zvichienderana nenzvimbo yecentromere, machromosome anogona kuiswa mumhando dzakasiyana-siyana: metacentric (centromere iri pakati), submetacentric (centromere iri pamusoro pepakati), acrocentric (centromere iri pedyo nemagumo), uye telocentric (centromere iri kumagumo).
Telomer
MaTelomere ndiwo magumo emachromosome akatsetseka, anoumbwa neDNA sequences dzinodzokororwa. MaTelomere anodzivirira magumo emachromosome kubva mukuora uye kusangana nemamwe machromosome. Nguva imwe neimwe apo sero rinopatsanuka, matelomere anopfupika, izvo zvine chekuita nekukwegura kwemasero. Enzyme inonzi telomerase inogona kuwedzera urefu hwematelomere, ichiita basa rakakosha mumasero anofanira kupatsanuka kakawanda, akadai semasero emasero emasero nemasero ekenza.
MaTelomere anoitawo basa guru pakuona hupenyu hwemasero. Kana maTelomere akanyanya kupfupika, masero anopinda muchikamu chinozivikanwa sekukura, uko anorega kupatsanurana asi anoramba achishanda. Iyi inzira yakakosha mukudzivirira kukura kwemasero kusingadzoreki uye kenza.
Chromatid
Chromatid iboka rakafanana rezvikamu zviviri zvakatsetseka zvinoumba chromosome yakadzokororwa. Sero risati rapatsanurwa, chromosome ine ma chromatids maviri akabatana panzvimbo inonzi centromere. Chromatid yega yega ine kopi chaiyo yeDNA, zvichiita kuti sero rega rega riwane majini anodiwa kuti rishande zvakanaka.
Maoko eP neQ
Machromosome anogona kukamurwa kuita zvikamu zviviri zvikuru zvinonzi maoko. Ruoko rupfupi runozivikanwa seruoko rweP, ukuwo ruoko rurefu runonzi ruoko rweQ. Zita iri rinobva muchiFrench, richinzi 'petit' zvichireva diki reruoko rweP. Kupatsanurwa uku kunobatsira mukugadzira mamapu emachromosomes uye kuziva nzvimbo yemajini chaiwo.
Matekinoroji akasiyana-siyana ekugadzira ma chromosome, akadai se banding staining uye fluorescein in situ hybridization (FISH), anoshandisa ma divisions aya kuti anyatsoona nzvimbo yemajini kana kusagadzikana mukati me genome. Izvi zvinobatsira mukutsvagisa majini uye kuongororwa kwemamiriro ezvinhu ane chekuita ne genome.
Basa uye Kukosha kweChromosomes
Machromosome haangotakuri majini chete; anodzorawo kugadzirwa kwemajini uye anovimbisa kugadzikana kwemajini kuburikidza nekupatsanurwa kwemasero kwakarongwa. Heano mamwe emabasa uye kukosha kwemachromosome:
1. Kutapurirana Kwemajini: Machromosome anobvumira kugara nhaka yezvinhu zvemajini kubva kuchizvarwa chimwe kuenda kune chinotevera, zvichiita kuti vana vagamuchire ruzivo rwemajini rwakakosha pakukura nekushanda.
2. Kudzora Majini: Nzvimbo yemajini ari pamachromosomes uye kudyidzana kwawo nemapuroteni ehistone nezvimwe zvinodzora zvinopesvedzera kuratidzwa kwemajini. Maumbirwo eChromatin anogona kunge akamanikana kana kuti asina kusimba, izvo zvinosarudza kana jini riri kushanda kana kuti risingashande.
3. Kudzora Kusiyana-siyana Kwemajini: Munguva ye meiosis, zviitiko zvakaita sekuyambuka nekuchinjana kwemajini pakati pema chromosome akafanana zvinowedzera kusiyana kwemajini, izvi zvakakosha pakushanduka-shanduka uye kugadziriswa.
4. Kugadzikana kweGenome: Maumbirwo e telomeres akakombama uye akatsetseka anobatsira kuchengetedza ruzivo rwemajini panguva yekudzokororwa kweDNA, zvichidzivirira kukuvara kana kurasikirwa neruzivo rwemajini.
Mhedziso
Kunzwisisa zvikamu zvemachromosomes nemabasa azvo kunopa ruzivo rwakadzama pamusoro pemaitiro ekugara nhaka uye mafambiro emagenes muzvinhu zvipenyu. Chikamu chimwe nechimwe chechromosome chine basa rakakosha uye rakakosha mukuchengetedza kusimba uye kuenderera mberi kwezvinhu zvemagenes, zvichiita kuti zvipenyu zvikure, zvikure, uye zvibereke zvinobudirira. Kubva kuma centromeres kusvika kuma telomeres, chikamu chimwe nechimwe chinoshanda pamwe chete kuona kuti ruzivo rwemagenes rwunochengetwa uye rwunoratidzwa nenzira yakarongeka, zvichisimbisa kushamisa uye kuomarara kwehupenyu padanho re microscopic. Tsvagiridzo yakawedzerwa inoramba ichiburitsa zvakavanzika nezvemachromosomes, izvo zvinogona kubatsira mukunzwisisa kwedu zvirwere zvemagenes uye mishonga mitsva inogona kushandiswa.
