1. Mitosis and Meiosis
Year 10 Biology

2. Mitosis and Meiosis Mitosis: -division of somatic (body) cells Meiosis
-division of gametes (sex cells – sperm and eggs)

3. Mitosis 2 identical daughter cells produced
Each daughter cell has the same number of chromosomes as the parent cell
1 set of cell division involved
End result – 2 diploid (or 2n) cells with 46 chromosomes in each

4. Mitosis
Interphase
Prophase
Metaphase
Anaphase
Telophase

5. Interphase Interesting things happen! Cell preparing to divide
Genetic material doubles (46 to 92)

6. Prophase Chromosome pair up! Chromosomes thicken and shorten
-become visible
-2 chromatids joined by a centromere
Nuclear membrane disintegrate
Spindle fibres form

8. Metaphase Chromosomes meet in the middle!
Chromosomes arrange at equator of cell
Become attached to spindle fibres by centromeres

10. Anaphase Chromosomes get pulled apart
Spindle fibres contract pulling chromatids to the opposite poles of the cell

11. Telophase Now there are two! Chromosomes uncoil
Spindle fibres disintegrate
Nucleur membrane forms
Cell divides

15. Meiosis 4 daughter cells produced
Each daughter cell has half the chromosomes of the parent (halpoid or ‘n’)
2 sets of cell division involved
End result – 4 cells with 23 chromosomes in each

16. Meiosis Interphase Prophase II Prophase Metaphase II
Metaphase Anaphase II
Anaphase Telophase II
Telophase