Meiosis II

Overall Hop up and down Three Blind Mice

Meiosis II Target: I will be able to identify and describe the key stages of Meiosis II. Meiosis II: Separation of the sister chromatids (the arms of a chromosome). Produces 4 daughter cells- each with 23 chromosomes. Daughter cells (one from the mother and one from the father) recombine at fertilization to produce an embryo with 46 chromosomes- the correct number for human life. Pg. 109

Phases of Meiosis II 1. Prophase II: Each new cell forms a spindle. Chromosomes move toward the center of the spindle.

2. Metaphase II: chromosomes attach to the spindle and line up on the equator.

3. Anaphase II: Chromosomes divide when Sister Chromatids pull apart. Now the chromosomes are single stranded.

4. Telophase II: the two daughter cells divide. Four haploid cells with single stranded chromosomes are produced. These gametes are genetically different from the parent cell that they came from.

Somatic (Body) Gamete (Sex) 2 4 Diploid Haploid Identical Different 46 Mitosis Meiosis   Type of Cell # of Cells Produced after division Haploid or Diploid cells produced Genetically identical or different cells produced # of chromosomes in human cells Somatic (Body) Gamete (Sex) 2 4 Diploid Haploid Identical Different 46 23

4. Telophase II: the two daughter cells divide. Four haploid cells with single stranded chromosomes are produced. These gametes are genetically different from the parent cell that they came from. Summary:

Breaking down meiosis Draw the product (result) of Meiosis II. Diagram Synapsis and Crossing Over Predict what would happen if the second division (Meiosis II) didn’t happen. (Why is it important that there are two divisions?). Draw the product (result) of Meiosis II. Pg. 108