2. CELL CYCLE

3. How many cells do we begin with?

4. 2

5. How do we get more?

6. Cell Cycle

7. INTERPHASE

8. G1 PHASE “gap 1” Phase period when cell growth and development occur

9. S PHASE “synthesis” Phase DNA replication / synthesis occurs

10. G2 PHASE “gap 2” Phase when organelles needed in cell division are made (centrioles, spindle fibers)

11. structure that contains genetic information (usually visible only in mitosis) CHROMOSOME

12. The set of 46 human chromosomes

13. the two identical parts on a chromosome CHROMATIDS

14. The middle part of the chromosome that holds together the sister chromatids CENTROMERE

17. MITOSIS

18. GOAL OF THE CELL CYCLE to create a new somatic cell exactly like the parent

19. MITOSIS process by which the nucleus of a cell is divided into two nuclei, each with the same number of chromosomes as the parent cell

20. 1. PROPHASE The longest phase Chromosomes appear Centrioles move to opposite ends of the cell Chromosomes attach to the spindle Nucleolus and nuclear membrane breaks down

21. PROPHASE (cont…) The longest phase Chromosomes appear Centrioles move to opposite ends of the cell Chromosomes attach to the spindle Nucleolus and nuclear membrane breaks down

22. 2. METAPHASE Shortest phase of mitosis Chromosomes line up at center of the cell

23. 3. ANAPHASE Centromeres split Sister chromotids separate to form individual chromosomes Anaphase ends when the movement of chromosomes stops

24. 4. TELOPHASE Chromosomes uncoil into chromatin Nuclear membrane reforms Spindle breaks apart

25. CYTOKINESIS The cytoplasm of the cell divides Forms two daughter cells that are exactly like the parent cell (each have one complete set of chromosomes)

26. Meiosis The process of cell division so that each new cell has 1/2 the number of chromosomes as the original.