Maumbirwo eChromosome muEukaryotic Nucleus
Machromosome maumbirwo akaomarara ari mukati menucleus yemasero eukaryotic. Anoita basa rakakosha mukuchengetedza, kudzokororwa, uye kuratidzwa kweruzivo rwemajini. Muchinyorwa chino, tichaongorora zvakadzama maumbirwo emachromosome eukaryotic, kunzwisisa zvikamu zvawo zvekutanga, mashandiro ekuronga, uye kukosha kwawo muchikamu chebiology yemasero nemolecular.
Nhanganyaya: Chii chinonzi Chromosome?
Machromosome maumbirwo akaita setsvimbo anoumbwa neDNA nemapuroteni. Mumasero eukaryotic, machromosome ari mukati menucleus. Sero remunhu, semuenzaniso, rine machromosome makumi mana nematanhatu, ane mapeya makumi maviri nematatu emachromosome akafanana.
Chimiro Chekutanga cheChromosomes
1. DNA: Chinhu chinonyanya kukosha pa chromosome iDNA (deoxyribonucleic acid). DNA imorekuru refu yepolymer inochengetedza ruzivo rwemajini. Morekuru yega yega yeDNA iri mu chromosome inounganidzwa uye inomanikidzwa kuita chimiro chakamanikana nerubatsiro rwemapuroteni.
2. MaHistone: Mapuroteni eHistone mapuroteni anoumba chimiro anoita basa rakakosha mukuronga DNA. DNA yakatenderedzwa netambo dzehistone, ichiumba maumbirwo anonzi nucleosomes. Nucleosome ine mabhesi maviri eDNA angangoita 147 akatenderedzwa nepakati pemapuroteni masere ehistone (histone octamer).
3. Chromatin: Musanganiswa weDNA nemapuroteni ehistone unonzi chromatin. Chromatin inogona kuoneka mumhando mbiri:
– Euchromatin: Nzvimbo isina kusimba, inoshanda pakunyora, inobvumira ma enzymes ekunyora nezvimwe zvinhu kuti zvisvike muDNA.
– Heterochromatin: Nzvimbo dzakatetepa uye dzisinganyanyi kushandiswa pakunyorwa, dzakafanana nemajini asingadiwi nesero mune mamwe mamiriro ezvinhu.
Pakeji yeChromosome: Kubva kuDNA kuenda kuChromosome
DNA refu ye eukaryotic inoda kuunganidzwa kuti ikwane mu nucleus yemasero madiki. Maitiro aya anosanganisira mazinga akasiyana-siyana ekurongeka:
1. Nucleosomes: Danho rekutanga rekurongeka kwambotaurwa. Nucleosomes dzinobatsira kuderedza hurefu hweDNA inosvikika nekuiputira muzvidimbu zvakaita semabhedhi.
2. 30 nm fibers: Nucleosomes dzinopetwazve kuita chromatin fibers dzine dhayamita inosvika 30 nm. Izvi zvinoita kuti DNA iwedzere kusimba uye inogona kuonda zvakanyanya pane dzimwe nhanho, senge panguva yekupatsanurwa kwemasero.
3. Nzvimbo Dzakachinjika: Aya mafiber e30 nm akasungirirwa muzvishwe zvinosungirirwa kumusana weprotein, zvichigadzira chimiro chakasimba. Zvishwe izvi zvinogona kurongwazve muzvishwe zvepamusoro.
4. Kuumbwa kweChromosome: Munguva yekupatsanurwa kwemasero kwe mitosis kana meiosis, machromosome anowedzera kuumbwa kusvika aonekwa nemaikorosikopu. Iyi ndiyo nhanho yepamusoro yekuumbwa, zvichiita kuti ruzivo rwemajini ruparadzirwe zvakanaka kumasero emwanasikana.
Basa Rinoshanda uye Kukosha kweChromosome Structure
1. Kubatanidzwa kweDNA: Maumbirwo emachromosomes anobvumira kudzokororwa kweDNA kwakarurama uye kunoshanda masero asati apatsanurwa. Chromosome yega yega inodzokororwa kuitira kuti sero rega rega rigamuchire seti yakazara yemachromosomes.
2. Kunyorwa kweDNA: Kuvapo kwe euchromatin yakareruka kunobvumira kuratidzwa kwemajini anodiwa pakushanda kwesero, nepo heterochromatin ichiita kuti majini asashande pasi pemamwe mamiriro ezvinhu.
3. Kugoverwa Kwemajini Munguva Yekupatsanurwa: Kuumbwa kwechromosome panguva ye mitosis uye meiosis kunoita kuti sero rega rega riwane seti yakazara yema chromosome, izvo zvakakosha pakukura, kubereka, uye kugadziriswa kwenyama.
4. Kudzora Majini: Marongerwo eDNA mumanucleosomes anokanganisa kugona kwemajini kuratidzwa. Kugadziriswa kwemakemikari kumahistones neDNA, senge methylation neacetylation, kunogona kuchinja kuwanikwa kwenzvimbo dzakati dzeDNA, zvichishanda senzira yakakosha yekudzora majini.
Maumbirwo eChromosome uye Zvirwere
Kukanganisika mumaumbirwo kana huwandu hwemachromosomes kunogona kukonzera zvirwere zvemajini. Zvimwe zvirwere zvinozivikanwa zvinosanganisira:
1. Down Syndrome: Inokonzerwa nekopi yekuwedzera yechromosome 21 (trisomy 21).
2. Gomarara: Kuchinja kwemaumbirwo emachromosome, akadai se translocations kana gene amplifications, kunogona kumutsa oncogenes kana kudzima majini anodzvinyirira tumor.
3. Klinefelter syndrome: Inoratidzwa nekuwanda kwechromosome X imwe kana kupfuura muvarume.
4. Turner Syndrome: Inokonzerwa ne monosomy X, apo mukadzi ane X chromosome imwe chete.
Tsvakurudzo Yeramangwana Mumunda weChromosomes
Kutsvagurudza kwakawanda pamusoro pemaumbirwo nemashandiro emakromosomu kunotsvaga kujekesa zvakanyanya zvirwere zvemajini negomarara, pamwe nekutsvaga nzira dzekugadzira mishonga mitsva. Semuenzaniso, kunzwisisa basa rekuchinja kwehysteresis mukudzora magene kwakavhura nzira itsva dzekugadzira mishonga inogona kuchinja kana kunanga shanduko idzi kurapa chirwere.
Mhedziso
Maumbirwo emachromosomes ari mu eukaryotic nucleus dhizaini yakaoma asi yakarongeka inoita kuti ruzivo rwemagene ruchengetwe, kutaurwa, uye kutapurirwa kwaro kwakanyatsonaka. Machromosomes haasi kungova tambo dzeDNA; iwo maturusi akarurama ehupenyu, achiratidza kuenzana kwakakwana pakati pekugadzikana kwemagene uye kuchinjika. Nekunzwisisa machromosomes, hatingovhuri zvakavanzika zvehupenyu chete asiwo tinovhura nzira yekufambira mberi mune ramangwana mune zvehutano uye biotechnology.
