Ch. 5.1- Cell Cycle

1. Ch. 5.1- Cell Cycle Cell Cycle and Cancer Cells

2. Stages of the cell cycle • 4 stages • Gap 1 (G1) • Synthesis • Gap 2 (G2) • Mitosis • A cell won’t proceed through the cycle until it’s ready • Prevents errors (cancer)

4. Gap 1 (G1) • First stage of cell cycle • Cell carries out its normal function • Skeletal cells contracts to move joints • Adrenal cells secrete hormones • Intestinal cells absorb nutrients, etc. • Cells increase in size & organelles increase in number • Cells must pass critical checkpoint before proceeding to DNA synthesis

6. Synthesis (S) • Second stage • Synthesis=“combining of parts to make a whole” • Cell makes a copy of its nuclear DNA • Contains 2 complete sets of DNA by end of the S stage

7. Gap 2 (G2) • Third stage • Continues to carry out normal functions • Additional growth occurs • Another critical checkpoint to ensure adequate cell size and that DNA is undamaged.

8. 2

9. Mitosis (M) • Fourth stage • Includes 2 processes • Mitosis= division of the nucleus and its contents • Cytokinesis= division of the cytoplasm • Results in 2 genetically identical daughter cells

10. Cells divide at different rates • Aligned to your body’s need for those cells • In human cells: S, G2, and M stages together take about 12 hours • Cell division is greater in children than adults • Their cell cycles are also shorter • Certain cells, such as neurons and lymphocytes, divide rarely • Usually in G0 stage

12. Exit Slip • Ch. 5.1 assessment pg. 137 • # 1, 2, 3, 5, & 6 • MUST BE IN COMPLETE SENTENCES AND YOUR OWN WORK!