1. The Cell Life Cycle

2. Learning Objectives Describe the cell life cycle.
Understand the role of cell division in the cell cycle.
Understand the process of terminal differentiation in cells
Describe mitosis and cellular differentiation.
Describe meiosis and contrast it with mitosis.

3. Cell division Cell division is the reproduction of cells
Apoptosis is the genetically controlled death of cells
Mitosis is the nuclear division of somatic cells
Meiosis produces sex cells

4. Interphase
Most somatic cells spend the majority of their lives in this phase
Interphase includes G1 S G2

5. The Cell Life Cycle

6. DNA Replication

7. Mitosis, or nuclear division, has four phases
Prophase
Metaphase
Anaphase
Telophase
During cytokinesis, the cytoplasm divides and cell division ends

8. Interphase, Mitosis, and Cytokinesis

9. Interphase, Mitosis, and Cytokinesis

10. Mitotic rate and cancer
Generally, the longer the life expectancy of the cell, the slower the mitotic rate
Stem cells undergo frequent mitoses
Growth factors can stimulate cell division
Abnormal cell division produces tumors or neoplasms
Benign
Malignant (invasive, and cancerous)
Spread via metastasis
Oncogenes

13. Chromosomes in Mitosis and Meiosis
Figure 28.6

16. Differentiation Process of specialization
Results from inactivation of particular genes
Produces populations of cells with limited capabilities
Differentiated cells form tissues

17. You should now be familiar with:
The cell life cycle.
Mitosis and cellular differentiation.
Terminal differentiation and the Go phase.
Meiosis and cell ploidy.