Kuberekana - mumwe doubling: kamuri kubva muchitokisi

Doubling paumbwe dzakafanana makopi maviri - kutanga zvakajairika mune chaivo gadziriro. Kazhinji doubling ichi anonzi kuberekana. Ekupedzisira anogona kuitika pamwero yakasiyana-siyana sangano kwenyaya - zvakananga kubva DNA kusvikira okutodza uye masero rose. Panguva iyoyowo, kana kwacho akaenda zvakanaka, vakawana akafanana muzvikamu zviviri. Kuberekana - mumwe doubling of ano zvishongo.

How chaizvo hapana

Kupfuura kunakidza uye mujinga zvimwe zvipenyu zvose runoonekwa kuti DNA kuberekana. Maitikiro kuti zvinoitika pamusoro mumatanho akawanda, rimwe nerimwe zvakarurama vachishoropodza, nokuti inaccuracy chirwise kwetunhu mapuroteni zvachose kukodzera kukodzera kushandiswa muchitokisi uye nhengo yose.

The pokutangira

Kuberekana rinotanga sero doubling DNA, chine mugumisiro doubling okutodza. Asi kuberekana - ndiyo repakona yose muitiro. Inoitwa muzvikamu zvitatu: Chokutanga, mharuro, chepiri elongation, uye Chechitatu, kugumiswa. Basa rinotanga enzayemu dzinonetsa pfungwa - replicators uye chete navo. Kutanga muna isiri nzvimbo yaizova kukanganisa yose muitiro. The enzayemu-tiwedzere zvaanopa simba chaizvo mapuroteni kuti vanoumba pre-kuberekana yakaoma inodiwa kuti DNA doubling. Pamberi chokuwanziridza DNA unotemwa muzvikamu vaviri chaicho makemikari.

The nopindirana cheni

Kana elongation pamusoro chizvaro zvakavakwa nopindirana mubereki cheni. Ndiko, mumwe kuti zvino anogona aumbe morekuru wakakwana. The kwacho inoguma ane kugumiswa kuti zvakare chinoitika pane imwe pfungwa. Pane chaiyo chairema - the replicon. Ndicho DNA chinyorwa kuti anovaka pamusoro nguva. DNA kuberekana - nheyo, pasina hazvigoni kudzokororwa okutodza. Ekupedzisira kunoitika apo sero vachigadzirira kugovera.

Protein sechiratidzo

Rinotanga chromosome doubling mumaawa mashomanana pashure zvaitika DNA doubling. Kuvakazve chromosome, tinoda rinovira kwete chete mutsva kubva deoxyribonucleic acid, asiwo mapuroteni kuti tiri chikamu chromosome midziyo, uye kwetunhu dzavo kunoda nguva. Fast kuberekana - chiratidzo kenza. Kana anoona mapuroteni yakawandisa, hunhu zvikuru muchitokisi weboka, chiremba anotanga kuridza aramu.

gwanza

Mune nedanho kuberekana chinhu chinokosha zvikuru - mu tsanga nzvimbo tichitarisa kwetunhu DNA itsva tinodzibata zvakaenzana, saka hapana kusarurama, izvo zvinogona kumutsa munhu yakawiriranwa simba. Zvikuru yakawanda pfungwa, kazhinji nehafu maviri dhazeni.

okutodza sei chaizvo achaparadzwa akarongeka napo kuitika muchitokisi mitosis kana meiosis. Muchiitiko chokutanga, kunoguma sero aizova zvatinosiita yakatarwa, rechipiri - hafu. Pashure pezvose, imwe hafu kuchaunza kamuri rechipiri shamwari iri pabonde kubereka. Kana meiosis pakarepo kuwana zvakakwana vanochengeta, gamete kana kuva unsustainable, kana chido vanamba mwana anorwara. Zvisinei, vana ava vachiri vanoberekwa kakawanda, pane kupfupfudzika mukuvamba pamuviri, amai vanogona kutora pamusoro pamwedzi ovulation kana ropa pakati ichitanga.