1. Cell Cycle Regulation

2. The Cell Cycle

5. What can be learned from this experiment? There are different signals (proteins) present that aid in the progression of the cell cycle Each stage has a different signal These signals are cdk-cyclin complexes

6. The Three Major Checkpoints

7. G1 – You can pass if… You have enough nutrients/energy You are large enough There is space available Your DNA is not damaged

8. G2 – You can pass if… DNA is not damaged Chromosomes are duplicated correctly

9. M – You can pass if… All chromosomes are attached properly to spindle fibers (Metaphase!)

10. What happens if cells don’t meet the requirements at a checkpoint? They die! Apoptosis – programmed cell death Or, repairs are made

11. G2 Check Point

12. How do Cdk and Cyclins function?

13. The levels of cyclin regulate the activity of the complex – Cdks are ALWAYS present

14. Why is it important for the cell cycle to be regulated? Uncontrolled cell division (failed checkpoints) can lead to CANCER cell formation