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H. Meiosis 1. Meiosis is a form of cell division that doubles the steps of mitosis and forms eggs and sperm. PMAT P2M2A2T2 The female produces an egg with an X chromosomes. The male produces 1X and 1Y chromosome. The Males sperm determines if you will have boys or girls. You have a 50/50 chance of getting a male or female 5. The formation of sperm is called spermatogenesis, the formation of eggs is called oogenesis.
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Phases of Meiosis G. When homologous chromosomes form (4 homologous chromosomes), you create a tetrads- 2. One major difference between mitosis and meiosis is crossing over and independent assortment. The chromosome pairs exchange information, this is crossing over. This is important because the resulting zygote will double the possibilities. This adds variation to evolution. Crossing-over occurs during meiosis. (1) Homologous chromosomes form a tetrad. (2) Chromatids cross over one another. (3) The crossed sections of the chromatids are exchanged.
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Meiosis source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwig hOumqcrJAhUU8mMKHd9mDX4QtwIIHzAA&url=http s%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3Dt oWK0fIyFlY&usg=AFQjCNFXd- 6vrI5OJmSfSjHyFYRcnKmFBw Meiosis is the process for making sex cells, gametes, sperm and eggs For genetics this adds to diversity
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Phases of Meiosis Spindle fibers attach to the chromosomes. MEIOSIS I
Metaphase I Spindle fibers attach to the chromosomes. MEIOSIS I Metaphase I - Spindle fibers attach to the chromosomes.
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Phases of Meiosis MEIOSIS I Anaphase I The fibers pull the homologous chromosomes toward opposite ends of the cell. MEIOSIS I Anaphase I - The fibers pull the homologous chromosomes toward opposite ends of the cell.
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Phases of Meiosis H. Nuclear membranes form.
MEIOSIS I Telophase I and Cytokinesis H. Nuclear membranes form. The cell separates into two cells. The two cells produced by meiosis I have chromosomes and alleles that are different from each other and from the diploid cell that entered meiosis I. MEIOSIS I Telophase I and Cytokinesis - Nuclear membranes form. The cell separates into two cells.
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Telophase II and Cytokinesis
Phases of Meiosis Meiosis II During meiosis, the number of chromosomes per cell is cut in half through the separation of the homologous chromosomes. The result of meiosis is 4 haploid cells that are genetically different from one another and from the original cell. Meiosis II Telophase I and Cytokinesis I Metaphase II Anaphase II Telophase II and Cytokinesis Prophase II
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Phases of Meiosis MEIOSIS II Prophase II Meiosis I results in two haploid (N) daughter cells, each with half the number of chromosomes as the original cell. MEIOSIS II Prophase II - Meiosis I results in two haploid (N) daughter cells, each with half the number of chromosomes as the original cell.
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Phases of Meiosis The chromosomes line up in the center of cell.
MEIOSIS II Metaphase II The chromosomes line up in the center of cell. MEIOSIS II Metaphase II - The chromosomes line up in a similar way to the metaphase state of mitosis.
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Phases of Meiosis MEIOSIS II Anaphase II The sister chromatids separate and move toward opposite ends of the cell. MEIOSIS II Anaphase II - The sister chromatids separate and move toward opposite ends of the cell.
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Phases of Meiosis MEIOSIS II Telophase II and Cytokinesis Meiosis II results in four haploid (N) daughter cells. MEIOSIS II Telophase II and Cytokinesis - Meiosis II results in four haploid (N) daughter cells.
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Gamete Formation Gamete Formation
In male animals, meiosis results in four equal-sized gametes called sperm. 23chromosomes from the mommy and 23 chromosomes from daddy. Meiosis produces four genetically different haploid cells. In males, meiosis results in four equal-sized gametes called sperm.
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Gamete Formation I. In many female animals, only one egg results from meiosis. The other three cells, called polar bodies, are usually not involved in reproduction. Oogenesis is the production of eggs. Meiosis produces four genetically different haploid cells. In females, only one large egg cell results from meiosis. The other three cells, called polar bodies, usually are not involved in reproduction.
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