1. CELL DIVISION As cells grow they must divide
Why?…(write your own answer)
DNA and cell division
All important info is in the DNA, so both daughter cells need a complete set, nothing missing, nothing extra
Chromatin starts out as spread out DNA molecules
Chromatin condenses into chromosomes by tightly folding

2. CELL DIVISION 1 chromatid Centromere 2 Identical copies
A Chromosome
1 chromatid Centromere
2 Identical copies
Each chromatid is identical to its partner

3. CELL CYCLE Open book to pg 102 Cell cycle is in 4 phases
G1 ; S ; G2 ; M
G1 - Most of cell’s growth and activity
S - DNA replicates
G2 - Final preparations for division
M - Cell division (mitosis) - Divided into 4 stages

4. INTERPHASE
In between cell divisions (G1 , S, and G2 phases)
Most of the cell’s life is in interphase
Chromosomes are in the form of chromatin (diffuse and invisible)
Each DNA replicates (makes a copy of itself)
Centrioles begin to move to poles of cell

5. PROPHASE First stage of actual mitosis
Chromatin condenses into chromosomes
Nuclear membrane disappears
Asters form at poles of cell (Not visible in plants)
Astral rays connect to centromeres on chromosomes
Asters and Astral rays together called the spindle
Astral rays
Chromosomes
Aster

6. METAPHASE Chromosomes are pulled by astral rays
Chromosomes line up along the equator of the cell

7. ANAPHASE Centromeres break
Each chromosome is pulled apart into separate chromatids
Spindle pulls chromatids toward poles

8. TELOPHASE Chromosomes disappear Nuclear membranes reappear
Spindle disappears
Cell membrane divides cell into 2 daughter cells
(In plants cell wall forms between daughter cells)
Daughter cells go back to interphase