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 Meiosis  is a special type of cell division which results in the formation of 4 haploid cells.

Meiosis consists of 2 divisions -  Meiosis1 and Meiosis 2 .

At the end of Meiosis 1,2 cells are formed whereas at the end of Meiosis 2 there is formation of 4 haploid cells.Meiosis reduces the chromosomal number by half,thus meiosis is also called reduction division.

The formation of haploid cells help in formation of gametes and fertilization thus giving rise to a new generation of Diploid organisms.Fertilization restores the diploid number of chromosomes,whereas Meiosis restores the haploid number of chromosomes.

Thus meiosis plays an important role to run the reproductive cycle of Prokaryotes and Eukaryotes.

DIFFERENT STAGES OF MEIOSIS-

 MEIOSIS1- 

 1.PROPHASE 1- 

 A.LEPTOTENE -Chromosomes are more uncoiled and assume a long thread like shape.  B.ZYGOTENE -  C.PACHYTENE-   D.DIPLOTENE -  D.DIAKINESIS- 
 * Chromosomes take up a specific orientation inside the nucleus
 * The end of chromosomes converge towards one side of nucleus where centromere lie.
 * The centrioles duplicate and daughter centrioles move towards opposite poles.
 * Pairing of homologous chromosomes i.e synapsis takes place which is exact and specific.
 * Paired chromosomes are joined by protein containing synaptonemal complex.
 * This complex extends the whole length of the chromosome and anchor on the either end to the outside.
 *  Recombination  or crossing over of chromosomes takes place.
 * Pair of chromosomes become twisted spirally around each other and cannot be distinguished separately.
 * The chromosomes split in between length wise to form 2 chromatids.
 * Two chromatids contain half DNA ,each become partial independent but still continue to be linked together by centromere.
 * Crossing over is reshuffling,redistribution and mutual exchange of hereditary material between one non-sister chromatids of each homologous chromosomes.
 *  Unpairing  or  desynapsis  of homologous chromosomes is started and chiasmata is first seen.Diakinesis.jpgatids of each tetrad is clearly visible.
 * Chromatids of paired homologous chromosomes join one or more discrete points called  chiasmata .
 * Unfolding of chromatids takes place allowing RNA synthesis and cellular growth.
 *  Bivalent chromosomes  become more condensed and evenly distributed in nucleus.
 * Nucleolous detatches and disappears.
 * Chiasmata moves from the centromere towards the end of chromosomes and intermediate chiasmata diminishes( terminalization ).
 * Chromatids are connected with  terminal chiasmata.