1. The Cell and Inheritance What is the difference between sexual and asexual reproduction? What are the differences between mitosis and meiosis? How many pairs of chromosomes do humans have?

2. Chromosome Theory of Inheritance

3. Genes are segments of DNA found on chromosomes Genes are passed from parents to offspring via chromosomes

4. Reproduction

5. Asexual reproduction: Genetic material from one parent New organism (or cell) is a copy of parent – all chromosomes are the same mitosis cloning Sexual reproduction: Genetic material from two parents – male = sperm – female = egg New organism is different than parents – chromosomes from both parents – 1/2 from male (father) – 1/2 from female (mother) meiosis

6. Chromosome Pairs

7. Humans have 23 pairs of chromosomes 46 total chromosomes Sex chromosomes are one pair – X from mother – X or Y from father female XX male XY

8. Meiosis PMAT I similar to mitosis 1 cell divides into 2 PMAT II 2 cells divide into 4 sex cells A sex cell is like a regular cell except it has ½ the chromosomes

9. Meiosis vs Mitosis 2 processes: PMAT I & II PMAT I: cell divides into 2 – NOT exact copies – Contain 46 chromosomes PMAT II: cells divide into 4 – Contain 23 chromosomes Result of Meiosis: 4 sex cells produced Each cell has only half the chromosomes 1 process: PMAT PMAT I: cell divides into 2 – exact copies – Contain 46 chromosomes Result of Mitosis: 2 body cells produced Cells are exactly like original