Cell Division

Create two identical cells from one cellPurposes:

Create a new organismGrowth and Repair

Binary FissionSingle Circular chromosome is replicatedCell doubles in sizeCell divides with one copy of chromosome in

cell

Prokaryotic Cell Division

Chromosome = two sections of identical DNA joined by a centromere

Sister Chromatids = 2 identical halves of a chromosome. When separated chromatids = chromsomes

Cell division in Eukaryotes (Vocab)

The Cell Cycle

Cell cycle = series of events that cells go through as they grow and divide

Begins and ends with formation of identical cells

What do cells need to do before they can divide?GrowReplicate DNA

Stages of the Cell Cycle•Two main phases – Interphase and M phase• Interphase is when the cell is not actively

dividing• Longest phase• broken into 3 stages: G1, S, G2

G1 = First growth phaseCell grows and carries out cell functionsCell creates RNA proteins and organellesExtended G1 phase (G0 phase) = no replication

Nerves, roots, stems

Stages of the Cell Cycle Continued

S = SynthesisDNA is replicated, cell now has two copies

DNA

*Each chromosome is copied. The new copy is joined to the old copy. Identical copies = sister chromatids. Together they form a chromosome.

Stages of the Cell Cycle Continued

G2 = Second Growth PhaseCell finishes preparation for divisionProtein RNA and macromolecules are made2x as much DNA in nucleus

Stages of the Cell Cycle Continued

M phase = DivisionDivision of the nucleusFollowed by division of the cytoplasm

(cytokinesis)Two cells are created from 1 cellShortest phase

Stages of the Cell Cycle Continued

Diagram and label the phases of Mitosis for a cell with 4 Chromosomes.

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