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Meiosis PowerPoint Presentation

Meiosis

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Meiosis

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    1. Meiosis

    2. Diploid 2 sets of chromosomes in a cell. from mom, from dad. 2n All body cells are diploid. Made by MITOSIS. Haploid 1 set of chromosomes in a cell. 1n All sex cells are haploid. Made by MEIOSIS.

    3. DIPLOID vs. HAPLOID 1n + 1n = 2n egg + sperm = new organism Haploid + Haploid = DIPLOID

    4. Gametes Another name for sex cells: egg & sperm

    5. Zygote A fertilized cell. 2 gametes that are now together.

    6. In case youve never seen it for realthis is human DNA.

    7. This is a DIPLOID cells DNA. (2n)

    8. This is a HAPLOID cells DNA. (1n)

    9. Meiosis The making of gametes (eggs & sperm). Cells contain the normal amount of chromosomes. (haploid)

    10. Meiosis

    11. Why is meiosis necessary? If the sex cells didnt have the amount of chromosomes, what would happen when the sperm & egg made a zygote? Answer: Each baby would have twice the number of chromosomes as the parents!!!

    12. What is produced in meiosis? 4 haploid cells (1n) Each cell is genetically different! Cool!

    14. Review Meiosis Facts Makes ____ cells genetically different from parent cell & from each other Makes _____ cells (1n or 2n?) Makes ________________ Used for ______________

    15. Spermatogenesis Makes 4 sperm cells.

    16. Oogenesis Makes 1 egg. (and 3 polar bodies)

    17. Spermatogenesis vs. Oogenesis

    18. What is different about meiosis? Many different variations in the gametes. ___________________________________ Divides twice, but only copies DNA once. ___________________________________

    19. Phases of Meiosis I P M A T P M A T Meiosis 1 Meiosis 2

    20. Meiosis

    21. Meiosis

    22. Mitosis vs Meiosis Interphase Interphase I DNA spread out as chromatin Nuclear membrane visible DNA copied during S phase

    23. Mitosis vs Meiosis Prophase Prophase I DNA scrunches into chromosomes Nuclear membrane disappears Centrioles appear

    24. Crossing Over Chromatid arms trade DNA with each other.

    25. Mitosis vs Meiosis Metaphase Metaphase I Chromosomes line up in middle

    26. Mitosis vs Meiosis Anaphase Anaphase I Chromatids split and move apart.

    27. Mitosis vs Meiosis Telophase Telophase I Two nuclei Nuclear membrane returns DNA spreads out as chromatin

    28. Mitosis vs Meiosis Cytokinesis Cytokinesis I Cytoplasm splits into 2 cells

    29. Mitosis vs Meiosis Prophase Prophase II DNA scrunches into chromosomes Nuclear membrane disappears Centrioles appear

    30. Mitosis vs Meiosis Metaphase Metaphase II Chromosomes line up in middle

    31. Mitosis vs Meiosis Anaphase Anaphase II Chromatids split and move apart

    32. Mitosis vs Meiosis Telophase Telophase II Two nuclei Nuclear membrane returns DNA spreads out as chromatin

    33. Mitosis vs Meiosis Cytokinesis Cytokinesis II Cytoplasm splits

    34. Mitosis vs Meiosis In Meiosis: (Prophase I) Homologous pairs match up.

    35. Meiosis

    36. The end. Really. Test date: How to succeed on GHS biology tests: Memorize the flashcards. Practice with friends, by yourself, or with family. Read the book. It is easy reading. Reading the text helps you understand the written part. Do all labs, homework, and worksheets. If you missed any days, make sure you made up any work!