1. Section 3-1
Meiosis

2. Chromosome Pairs (Homologous Chromosomes)

3. Diploid Chromosome # = 46

4. Meiosis
Reductive chromosomal division: Reduces diploid number (46) to haploid (23).
Egg (23 chromosomes).
Sperm (23 chromosomes).
Fertilization: Egg + Sperm produces diploid zygote (46 chromosomes).

5. Interphase Before Meiosis
Replication of chromosomes.
Chromosomes composed of two sister chromatids.

6. Meiosis I

7. Meiosis I Major effect:
Recombination (or crossing-over): Generation of genetic diversity.
Separation of homologous chromosomes.

8. Meiosis II

9. Meiosis II Major effect: Separation of sister chromatids.
Production of haploid gametes.

10. Genetic Implications of Meiosis
Synapsis or pairing of homologous chromosomes: Necessary for crossing over or recombination.
Independent assortment of chromosomes.
Shuffling of the genetic deck of cards.