1. Meiosis I

2. Excellency
Top Hat
Stay Overnight

3. Meiosis I
Target: I will be able to identify and describe the key stages of Meiosis I.
Meiosis: Cell division that results in gametes with half the number of chromosomes as the parent cell.
Allows offspring to be genetically different from the parents.  
Gametes: Sex cells- Sperm and egg.
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4. Homologous Chromosomes: Identical chromosomes that make up each pair in Meiosis.
Meiosis I: Separation of homologous chromosomes.

5. Diploid: cells that contain two of every chromosome.
Haploid: cells that contain one of every chromosome.
1N.

6. Phases of Meiosis I:
1. Prophase I: Chromosomes are double stranded so they are diploid.
The nuclear membrane disappears and spindle fibers form.

7. Synapsis: homologous chromosomes pair up and attach at their centromeres (called tetrads- groups of 4 chromosomes).
Crossing Over: exchange of genetic material between homologous chromosomes.

8. 2. Metaphase I: tetrads line up on the equator.

9. 3. Anaphase I: The homologous chromosomes pull apart.

10. 4. Telophase I: cytoplasm divides forming 2 new haploid cells (1N).
Half the number of chromosomes than the parent cell, but double stranded.

12. 4. Telophase I: cytoplasm divides forming 2 new haploid cells (1N).
Half the number of chromosomes than the parent cell, but double stranded.
Summary:

13. If I were a Gamete…
Pretend that you are gamete cell going through Meiosis I
Tell me which cell you are (sperm or egg) and then describe what is happening to you at each phase.
*Use good grammar.
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