1. Chromosomes

2. Chromosomes contain all of our genetic information. CHROMOSOMES contain GENES which are made from DNA. Humans have 23 PAIRS OF CHROMOSOMES. These chromosomes are the INSTRUCTIONS FOR EVERYTHING in our body.

3. Chromosome Maps and Gene Maps

4. Autosomal Genetic Disorders – Down Syndrome

5. Sex-Linked Genetic Disorders

7. Mitosis

8. MITOSIS 2N ALL CELLS AND DNA IDENTICAL

9. Mitosis  Occurs in Somatic (body) cells  Used in growth & repair of body cells, Asexual reproduction

10. Cells will turn into this  Daughter cells will turn into fully functional body cells (liver cells, muscle cells, etc.)

11. Meiosis 2N 1N Division I Division II 4 NEW GENETICALLY DIFFERENT CELLS

12. Meiosis

13. OOccurs in Gametes (sex cells) UUsed in Sexual reproduction

14. Sperm and Egg Meiosis

15. Cells will turn into this  Males – 4 sperm  Females – 1 egg and 3 polar bodies

16. Chromosome Number DDivides in half (46 to 23 chromosomes) SSperm (23) and egg (23) combine to form a zygote (46) during fertilization TThis ensures chromosome # is right

17. Genetic material  Genetic Variation caused by crossing over – chromatids overlap, break apart, and reattach to form new combinations of DNA

18. MitosisMeiosis PurposeGrowth,RepairSexual Reproduction Chromosome #2N to 2N2N to 1N # of cells produced 24 # of divisions12 Genetic Material Stays the sameVariation in gametes Where it occursSomatic cellsGametes