1. Regulating The Cell Cycle

2. Warm Up – The Cell Cycle The cell spends 80% of the time in _______________ and 20% of the time in ________________ What are the steps in mitosis?

3. Key Concept How is the cell cycle regulated? How do cells know when to divide? How do you heal when you break a bone?

4. Regulate the Cell Cycle Cyclin: A protein that regulates the cell cycle Tells the cell when to begin mitosis

5. Growth Factors Growth factors stimulate the growth and division of cells When is this important?

6. How Does a Cell Die? 1. Accident or injury 2. Apoptosis: Programmed cell death

7. What is Cancer? How have we been affected by cancer? How are cancer cells different from other cells? Why doesn’t everyone get cancer?

8. Cancer Cancer: Uncontrollable cell growth Cancer cells don’t respond to signals that regulate growth of cells Tumor: Mass of cells that divide uncontrollably

9. What Causes Cancer? Defects in genes that regulate cell growth and division. Example: Defect in gene p53, which normally stops the cell cycle until all chromosomes are properly replicated.

10. How Cancers Spread: Metastasis Cancerous cells lose control and continue to grow & divide, producing tumors which can metastasize (spread to other parts of the body)

11. Think & Apply… How are cancer cells different from normal cells? When researchers develop drugs, what characteristic of cancer cells do you think they target?