Puas yog hlwb 4n tom qab S theem?
Puas yog hlwb 4n tom qab S theem?

Video: Puas yog hlwb 4n tom qab S theem?

Video: Puas yog hlwb 4n tom qab S theem?
Video: ZAj DUB - Koj puas tu siab li kuv ( Official MV + Karaoke ) Ib ntsais muag 2 2024, Kaum ib hlis
Anonim

Thaum S theem , replication nce DNA cov ntsiab lus ntawm cov cell od2n ua 4 ib n , yog li hlwb hauv S muaj DNA cov ntsiab lus ntawm 2n mus rau 4 ib n . DNA cov ntsiab lus ces tseem nyob ntawm 4 ib n rau hlwb hauv G2 thiab M, txo rau 2n tom qab cytokinesis.

Ua li no, nyob rau theem twg ntawm lub voj voog ntawm tes yuav muaj 4n DNA cov ntsiab lus?

S Phase

Ib sab saum toj no, S theem sawv rau dab tsi? S theem (Synthesis Theem ) yog theem ntawm lub voj voog ntawm tes uas DNA yog replicated, tshwm sim ntawm G1 theem thiab G2 theem . Txij li qhov tseeb duplication ntawm genome yog qhov tseem ceeb rau kev ua tiav cell division, cov txheej txheem uas tshwm sim thaum lub sij hawm S - theem yog nruj tswj hwm thiab dav kev txuag.

Tsis tas li ntawd, muaj pes tsawg chromosomes tom qab S theem?

Nco qab tias muaj ob txoj kev faib thaum lub sij hawm meiosis: meiosis I thiab meiosis II. Cov khoom siv caj ces ntawm lub xovtooj yog duplicated thaum S theem ntawm interphase ib yam li nws tau nrog mitosis ua rau 46 chromosome ua thiab 92 chromatids thaum Prophase I thiab Metaphase I.

Qhov kawg tshwm sim ntawm S theem hauv lub voj voog ntawm tes yog dab tsi?

Interphase yog tsim los ntawm G1 Phase ( cell kev loj hlob), ua raws li S theem (DNA synthesis), ua raws li G2 Phase ( cell kev loj hlob). Nyob ntawm kawg ntawm interphase los ntawm mitotic theem , uas yog ua los ntawm mob mitosis thiab cytokinesis thiab ua rau kev tsim ntawm ob tug ntxhais hlwb.

Pom zoo: