Mitosis & Cell Division
Mitosis - The division of the nucleus that results in identical complete copies of chromosomes packaged into two new nuclei
Cytokinesis - The division of the cytoplasm that results in two daughter cells
Why do Cells Divide?
· Growth
· Reproduction (in single celled organisms)
· Repair
Some Cells never divide, others divide frequently.
The Cell Cycle
Mitosis
Interphase(technically not part of mitosis, but it is included in the cell cycle)
Cell is in a resting phase, performing cell functions / DNA replicates (copies)
Organelles double in number, to prepare for division
G1 - First growth / S - synthesis (copy DNA)
G2 - Second growth / Prophase
Spindle forms
Centrioles move to opposite poles
Chromosomes become visible
Nuclear membrane breaks down in prometaphase / Prometaphase
Microtubules of spindle attach to kinetochore on chromosomes
Metaphase
Chromosomes line up along the equator / Anaphase
Centromeres divide
Chromatids separate and move to opposite poles / Telophase
Nuclear membrane forms around each group of chromosomes
Chromosomes unwind
Cytokinesis begins - cell pinches inward and forms two daughter cells.
Mitosis produces 2 daughter cells. These two daughter cells contain the exact same number of chromosomes as the original parent cell. Daughter cells are DIPLOID