安徽医科大学：《医学细胞生物学》课程教学资源（课件讲稿，打印版）Cell division and cell cycle

Cell division and cell cycle Daughter G, cells Chromosome condensation Nuclear envelope breakdown Chromosome Chromosome segregation decondensation Reformation of Go Chromatids nuclear envelope Cytokinesis G DNA synthesis This document is produced by trial version of Print2Flash.Visit www.print2flash.com for more information

Outline 1.Cell division 2.Cell cycle and regulation 2 This document is produced by trial version of Print2Flash.Visit www.print2flash.com for more information

Section 1.Cell division amitosis (direct division) mitosis (indirect division) meiosis (mature division) 蛙的红细胞的无丝分裂 This document is produced by trial version of Print2Flash.Visit www.print2flash.com for more information

1.Mitosis (indirect division) Equatorial plate centrosome Interphase Prophase Metaphase y 0m Cytokinesis Telophase Anaphase This document is produced by trial version of Print2Flash.Visit www.print2flash.com for more information

(1)Prophase: Chromatin begins to condense and coil into double rod-shaped structures called chromosomes in which the chromatin becomes visible,both sides of the centromere is attached to the kinetochore,histone are phosphorylated. Nucleolus disassembled,rRNA synthesis stops. Interphase Interphase-prophase transition Nuclear Nucleus envelope Centrosomes Nucleolus Chromatin The nucleus replicates its The chromatin DNA and centrosomes begins to coil This document is produced by trial version of Print2Flash.Visit www.print2flash.com for more informatior

6 This document is produced by trial version of Print2Flash.Visit www.print2flash.com for more information

(2)prometaphase Nuclear membrane breaks apart(phosphorylation of lamins by MPF) ■Spindle appears Chromosome alignment(microtubules and motor proteins) Prophase Prometaphase Chromatids of Developing chromosomes spindle Aster The chromatin continues to The nuclear envelope breaks coil and supercoil,making down.Kinetochore microtub- the chromatin more and ules appear and interact with more compact.The chromo- the polar microtubules of the somes consist of identical, spindle,resulting in movement paired chromatids of the chromosomes This document is produced by trial version of Print2Flash.Visit www.print2flash.com for more information

Prometaphase This document is produced by trial version of Print2Flash.Visit www.print2flash.com for more information

(3)Metaphase: ■ Chromosomes reach the maximum degree of aggregation. All centromeres are arranged on the equatorial plate, microtubules at both sides balanced on length and power. Mitotic apparatus:chromosomes,aster,centrosomes and spindle. Metaphase Anaphase Equatorial Daughter chromosomes (metaphase)plate Each centromere divides,and the new chromosomes (each The duplicated centromere derived from one member of regions connecting paired one of the sets of paired chromatids become aligned chromatids)begin to move in a plane atthe cell's equator toward the poles This document is produced by trial version of Print2Flash.Visit www.print2flash.com for more information

(a (b) Zone of interdigitation Kinetochore MT Kinetochore Astral M - +) Pole Polar MTs Aster Spindle Aste 10 This document is produced by trial version of Print2Flash.Visit www.print2flash.com for more information