Mitosis is the process of cell division that produces two daughter cells from one parent cell. It allows for the growth and repair of organisms. The key stages of mitosis are prophase, metaphase, anaphase and telophase, where the cell's genetic material is duplicated and separated. Cytokinesis then divides the cytoplasm, forming two identical daughter cells each with the full set of chromosomes. Mitosis ensures the constant replenishing of cells while preserving the organism's DNA.

1. BIOLOGY
Unit 4 Notes:
Mitosis

2. (1) What is Mitosis?
• Cell division for non-sex cells.
• Non-Sex Cells:
– Are also called Somatic Cells.
– Examples Skin, Hair, Muscle, Bone, etc.

3. (2) What happens during Mitosis?
• Cells make exact copies of themselves.
• Start with 1 cell, and end up with 2 identical
copies.
• Start “2n” or “Diploid”  End “2n” or “Diploid”
• 2n = Diploid = Full set of genetic information
– In Humans this means a full set of 46 chromosomes (or
23 pairs).

4. (3) Mitosis Phases
1. Prophase
2. Metaphase
3. Anaphase
4. Telophase
5. Cytokinesis

5. (4) Prophase
• Nuclear membrane dissolves.
• DNA condenses into chromatin and then
chromosomes.
• Centrioles and Spindle Fibers inside the cell
prepares to move genetic material.
• Terms:
– DNA = Basic genetic molecule
– Chromatin = Wound up DNA
– Chromosomes = Wound up Chromatin

6. (5) Metaphase
• Pairs of sister chromatids line up at the metaphase
plate.
• Terms:
– Sister Chromatids: Identical copies of DNA or chunks of
chromosomes.
– Metaphase Plate: The very center of the cell.

7. (6) Anaphase
• Pairs of sister chromatids separate to opposite
ends of the

8. (7) Telophase
• The sister chromatids are fully separated.
• The nucleus starts to reform around genetic
material.
• The chromosomes unwind fully.

9. (8) Cytokinesis
• The cytoplasm splits.
• The cell membrane splits and reforms around the 2
new cells.
• Terms:
– Cytoplasm: The matrix filling the inside of cells.