1. Meiosis Cell division that produces sex cells.

2. 2 kinds of reproduction Asexual = one make two Sexual = two makes one

3. Sex cells are different from normal body cells. Function-to produce an organism Function-to produce an organism Human sex cells have only 23 chromosomes pairs (46 total) Human sex cells have only 23 chromosomes pairs (46 total)

4. Homologous Chromosomes Chromosomes with matching information (example hair color w/hair color)

5. Male = sperm Female = egg or ova Each sperm and each egg has only one of the chromosomes for each homologous pair.

6. Why is it important that sex cells have ½ the usual number of chromosomes?

7. Answer… Each parent donates ½ to make sure the offspring gets the right amount

8. Each body cell must have the entire set of 46 chromosomes in order to grow and function properly.

9. Turn to page 116-117 in your Life Science book Meiosis You Tube Demonstration Meiosis You Tube Demonstration

10. Step 1: Homologous pair copies itself and makes a shorten & thicken version of itself. …just like mitosis

11. Step 2: The chromosome pair line up next to each other in the center of the cell. …sound familiar?

12. Step 3: The pairs then separate and move to opposite ends of the cell. …hmmm

13. Step 4: 2 cells form- each with ½ the number of chromosomes. * Keep in mind that each chromosome is still double stranded.

14. Step 5: The double sided chromosomes move to the center of the cell. The centromeres split and the two strand of each chromosome separate. The two strand move to the opposite ends of the cell. …Rinse, Lather, & Repeat

15. When sex cells are made the chromosomes are copied once, and then the nucleus divides twice. The result: sperm and eggs have half the number of chromosomes found in a normal body cell.

16. P.S. The book will show 8 steps.