Meiosis

Alex Kingsley

Meiosis 1

Interphase 1 - Cells undergo a round of DNA replicaition, forming duplicate chromosomes.
Prophase 1 - Each chromosome pairs with its corresponding homologous chromosome to form a tetrad.
Metaphase 1 - Spindle fibers attach to the chromosomes.
Anaphase 1 - The fibers pull the homologous chromosomes toward opposite ends of the cell.
Telophase 1 and Cytokinesis - Nuclear membranes form. The cell separates into two cells.

Meiosis 2

Prophase 2 - Meiosis 1 results in two haploid daughter cells, each with half the number of chromosomes as the original cell.
Metaphase 2 - The chromosomes line up in a simular way to the metaphase stage of mitosis.
Anaphase 2 - The sister chromatids separate and move toward opposite ends of the cell.
Telophase 2 and Cytokinesis - Meiosis 2 results in four haploid daqughter cells.

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Meiosis is the same as mitosis except mitosis only goes through the 1st steps. it dosnt repeat them.
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Nondisjunction is error in meiosis in which homologous chromosomes fail to separate.

Karyotypes are photographs of chromosomes grouped in order in pairs.
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Genetic recombination is the process by which a molecule of nucleic acid is broken and then joined to a different one.

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http://www.biostudio.com/d_%20Meiotic%20Nondisjunction%20Meiosis%20I.htm

Links:

http://en.wikipedia.org/wiki/Genetic_recombination

http://www.biologyinmotion.com/cell_division/index.html

http://biology.clc.uc.edu/courses/bio104/meiosis.htm