Phases of the Cell CyclePhases of the Cell Cycle

Interphase and MitosisInterphase and Mitosis

InterphaseInterphase

G1G1: Cell Grows: Cell Grows

SS: DNA is copied (to produce a diploid #: DNA is copied (to produce a diploid #

of chromosomes.of chromosomes.

G2:G2: Cell nucleus prepares to divide Cell nucleus prepares to divide

The cell spends 90% of its time in interphase.The cell spends 90% of its time in interphase.

Figure of InterphaseFigure of Interphase

ProphaseProphase

Chromosomes coil and become visible.Chromosomes coil and become visible.

Nuclear envelope disappears.Nuclear envelope disappears.

Spindle fibers form from centrioles.Spindle fibers form from centrioles.

Figure of ProphaseFigure of Prophase

MetaphaseMetaphase

Chromosomes line up along the center of Chromosomes line up along the center of the cell.the cell.

Spindle fibers attach to the centromere of Spindle fibers attach to the centromere of each chromosome.each chromosome.

Figure of MetaphaseFigure of Metaphase

AnaphaseAnaphase

Centromeres divide.Centromeres divide.

Sister chromatids move to opposite poles Sister chromatids move to opposite poles by way of spindle fibers.by way of spindle fibers.

Figure of AnaphaseFigure of Anaphase

TelophaseTelophase

Nuclear envelope reforms around Nuclear envelope reforms around chromosomes.chromosomes.

Spindle fibers dissolve.Spindle fibers dissolve.2 genetically identical haploid cells are 2 genetically identical haploid cells are

produced.produced.Cytokinesis occurs : cytoplasm divides Cytokinesis occurs : cytoplasm divides

and cell membrane grows to enclose each and cell membrane grows to enclose each cell. 2 cells result.cell. 2 cells result.

Figure of TelophaseFigure of Telophase

CytokinesisCytokinesis

MisconceptionsMisconceptions

Mitosis does produce 2 cells that are Mitosis does produce 2 cells that are identical to the parent cell.identical to the parent cell.

The 2 daughter cells are haploid (n) in The 2 daughter cells are haploid (n) in number of chromosomes after telophase, number of chromosomes after telophase, however, during interphase the DNA is however, during interphase the DNA is copied to produce a diploid (2n) number of copied to produce a diploid (2n) number of chromosomes.chromosomes.

Misconceptions, cont.Misconceptions, cont.

The The Cell Cycle Cell Cycle include Interphase, include Interphase, Prophase, Metaphase, Anaphase, & Prophase, Metaphase, Anaphase, & Telophase/Cytokinesis.Telophase/Cytokinesis.

Mitosis (m phase) Mitosis (m phase) includes Prophase, includes Prophase, Metaphase, Anaphase, Metaphase, Anaphase, Telophase/Cytokinesis.Telophase/Cytokinesis.