Meiosis http://www.biology.arizona.edu/cell_bio/tutorials/meiosis/main.html

Interphase Same as in mitosis Growth and Replication G1 – cell growth G2 – replication of chromosoms G3 – growth and preparation for cell division

Chromosomes

Karotype

Prophase I Chromosomes thicken and condense ( become visible) Centrioles move to the poles Nuclear envelop disappears Homologous chromosomes come together during SYNAPSIS to form a TETRAD Crossing-over occurs

Metaphase I Chromosomes move to the equator as a tetrad Spindle fibers attach to chromosome

Anaphase I Spindle fibers shorten Homologous chromosomes separate and move to the poles

Telophase I / Cytokinesis Cell membrane begins to pinch in Nuclear membrane reappears The cytoplasm divides Formation of cell membrane Results in two haploid daughter cells

Meiosis II Proceeds just as mitosis with the exception of chromosome replication. THEY DO NOT REPLICATE AGAIN!!! Prophase II Metaphase II Anaphase II Telophase II Cytokinesis

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