Cell Division 8.2 (p. 148-151)

1. Cell Division 8.2 (p. 148-151) • Binary fission= prokaryotic cell (e.g. bacterium) splits into 2 identical cells • Single, circular chromosome is copied • Cell grows then divides into 2 identical cells (asexual)

6. Cell Division 8.2 (p. 148-151) • Cell cycle = repeating set of events of a eukaryotic cell • INTERPHASE = between phase • PROPHASE = before phase • METAPHASE = next to each other phase • ANAPHASE = opposite phase • TELOPHASE = reorganize phase I P M A T

8. Cell Division 8.2 (p. 148-151) • Mitosis = division of the cell into 2 identical copies (P,M,A,T) • Sexually reproducing organisms

9. Cell Division 8.2 (p. 148-151) • Interphase = time between cell divisions • Most of cell’s life spent in interphase • Cell grows (G1 phase) • Cell makes a full copy of the DNA (S phase) • Cell prepares to divide (G2 phase) What are the 3 subphases of Interphase?

10. Cell Division 8.2 (p. 148-151) • Prophase = 1st phase of mitosis (preparation) • DNA shortens and coils into tight chromosomes (pair of socks) • Nuclear membrane disappears • Centrosomes form at opposite poles of cell • Spindle fibers attach like strings to the centromeres to pull chromosomes apart What is the difference between centromeres and centrosomes?

12. Cell Division 8.2 (p. 148-151) • Metaphase = spindle fibers move the chromosomes to the equator of the cell Where is the equator of the cell?

13. Cell Division 8.2 (p. 148-151) • Anaphase = spindle fibers pull chromatids toward opposite poles Where are the poles of a cell?

14. Cell Division 8.2 (p. 148-151) • Telophase = chromatids loosen coils and nucleus begins to form again • Cytokinesis = cell pinches in middle to separate into 2 • In plant cells a new cell wall forms in the middle

17. Cell Division 8.2 (p. 148-151)

18. Cell Division 8.2 (p. 148-151)