Amber+Webber+-+What+is+meiosis+and+the+steps+during+each+phase?

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In this wiki you will learn the steps of Meiosis and what happens in these steps.

**//__http://www.phschool.com/science/biology_place/biocoach/meiosis/overview.html__//**

Meiosis is a process where a parent cells divides to produces cells that have half the genetic material that the parent has. There are 4 steps. The steps are prophase, metaphase , anaphase , and telophase.

Prophase.

__//**http://www.phschool.com/science/biology_place/biocoach/meiosis/proi.html**//__ Prophase, is the first stage of meiosis. Prophase is the longest phase in meiosis. In the beginning the chromosomes have already duplicated. The homologous chromosomes that have been divided pair and then they cross over. The nuclear envelope and the nucleolus disappear in prophase.

Metaphase.

__**//http://www.phschool.com/science/biology_place/biocoach/meiosis/metai.html//**__

Metaphase, is the second phase of meiosis. In metaphase, centrioles are at opposite poles of the cell. The homologous chromosome pairs arrange on a plane equidistant from the poles, this is called the metaphase plate. The spindle fibers from one pole attach to one chromosome of each pair and fibers from the opposite pole attach to the homologous chromosome. In the metaphase stage, there is a 50-50 chance of the daughter to get either the mother’s or father’s homologue for each chromosome.

Anaphase.

__//**http://www.phschool.com/science/biology_place/biocoach/meiosis/anai.html**//__ Anaphase is third stage of meiosis. Anaphase starts when two chromosomes pairs separate and move back to the opposite poles of the cell. Each daughter cell is now haploid, but both of the chromosomes have two chromatids. Since the chromosomes from each parent can go to either poles this means it's increased genetic diversity.

Telophase.

__//**http://www.phschool.com/science/biology_place/biocoach/meiosis/teloi.html**//__ Telophase is the fourth step. In telophase the chromosome pairs finish there move to the poles, this is a result of the action of the spindle. Telophase is also called the clean up stage. Then, a nuclear envelope may reform or the cell could quickly begin to start meiosis II. There are 2 chromosomes unlike mitosis.

Meisosis 2.

Prophase 2 the cell comes directly from telophase 1 to prophase 2. In prophase 2 the spindle is set up and the nuclear envelope is dissolved. Metaphase 2, both daughter cells complete the formation of a spindle apparatus. Single chromosome line up on the metaphase plate. In Anaphase 2, the centromeres separate, and the two chromatids of both chromosomes move to opposite poles. Now, the separate chromatids are called chromosomes in their own right. In telophase 2, the nuclear envelope forms around the sets of chromosomes. Then cytokinesis takes place, and produces four daughter cells, each with a haploid.

Resources.

"The Process Of Meiosis.." //www.phschool.com//. Pearson Education INC., Web. 1 June 2009. .

Burd, Gail. "Meiosis Tutorial." //www.biology.arizona.edu//. N.p., Apr. 1997. Web. 1 July 2004. .