1. Cell division Mitosis: for growth and healing, ADDS NEW CELLS
Results in exact copies of the parent cell, all chromosomes present
Meiosis: for gamete formation (egg and sperm) cuts the chromosome number in half so sperm and egg can form zygote

2. Mitosis
Cell division

3. Phases of Mitosis This proceeds without any pauses between phases
The phases are somewhat arbitrary, to help us identify what is happening
All phases do not take an equal amount of time; some are longer than others

4. Prophase Chromosomes become visible Nuclear membrane disappears
(Chromosomes are already copied)

5. Metaphase Chromosomes attach to spindle fibers
Chromosomes are pulled to line up on equator of cell
Single file

6. Anaphase
Chromatids separate
Move to opposite poles

7. Telophase Opposite of prophase Chromosomes reach the poles
Chromosomes uncoil and return to chromatin
Nuclear membrane reappears

8. Cell Differentiation
One zygote will develop into 260 specialized cell types
A bone cell is different from a blood cell, a nerve cell, a gland cell that secretes a substance, etc.

9. Cell Differentiation Stem Cells
Have the ability to divide without specializing
They can become any kind of cell after several divisions
One stem cell divides into another stem cell and a PROGENITOR CELL, which is partially specialized