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first let us Define meiosis with this
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image from a parent cell four cells are
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formed after two divisions and the
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chromosome number of this toted cells is
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reduced to half as you see here compared
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to this parent cell so four cells with
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half chromosome number now we can Define
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meiosis as a type of cell division that
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produces four hloy cells with half the
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chromosome number from a deploy parent
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meiosis is essential for sexual
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reproduction as it forms egg cells and
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sperm cells and also contributes to
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genetic diversity now let us understand
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the stages of meiosis as we said there
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are two divisions the first division is
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the meiosis one the first stage is the
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prophase one of meiosis one during this
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stage the chromosome condenses and
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becomes visible homologous chromosomes
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pair up so this is the homologous
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these are chromosomes with similar
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length Gene position and cic position
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one from the father and the other from
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the mother this forms
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tetrads as it is made up of four
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chromatids 1 2 3 4 that's why it is
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called as tetrads so homologous
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chromosomes pair up or synapse during
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meiosis one of proace one crossing over
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or exchange of segments between these
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homologous chromosomes takes place
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during this stage that cont contributes
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to genetic diversity nuclear envelop
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breaks down spindled fibers
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form the next phase is a metaphase
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during metaphase nucleus disappears The
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stret Rods or homologous chromosomes
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aligns at the center or at the metaphase
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plate spindal fibers attaches to the
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centromere of this homologous
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chromosomes the next phase is the
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anafase 1 during anaf phase 1 homologous
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chromosomes are pulled to the opposite
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BS of the cell by the activity of the
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spindal fibers as you see here and the
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final stage of meiosis 1 is a te of
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phase 1 during te of phase 1 chromosomes
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reach the pulse nuclear envelope reforms
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division of cytoplasm or cyesis occurs
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resulting in the formation of two haid
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daughter cells so from a deployed parent
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cell two hlid cells are formed that is
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why meiosis one is called as reduction
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division as two hloy cells are formed
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from a diploid parent cell so in this
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division the chromosome number is
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reduced to half the second division is a
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meosis 2 in meosis 2 the first stage is
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propas 2 where chromosomes condense
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again in each of these holoid cells
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spindle fibers forms just like propas
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one then there is metaphase 2 these
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chromosomes align at the center or at
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the metaphase plate in each holoid cell
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spindal fibers attaches to the
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chromatids the next stage is anaas 2
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where the sister chromatids are pulled
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apart to the opposite poles of the cell
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by the activity of a spindal fibers and
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the Final Phase is a tillo phase 2 where
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chromatids reaches the poles nuclear
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envelop reforms and cyto minosis or
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division of cytoplasm occurs resulting
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in the formation of four genetically
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distinct haid cells as you see here 1 2
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3 and four so in meosis 2 is just like
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mitosis two haid cells divides to form
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four haid cells just like mitosis that's
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why meiosis 2 is also called as
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equational division or it is similar to
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mitosis the major difference between
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meiosis 1 and meosis 2 is in meiosis 1
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during anaas homologous chromosomes are
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separated Ed whereas in meiosis 2 as you
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see here during anaas 2 sister
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chromatids are separated now we can
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summarize meiosis as a type of division
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that results in the formation of four
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hloy cells from a deploy parent cell or
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four cells with half the number of
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chromosomes in comparison with the
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parent cell hope you are clear where do
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mitosis and meosis occur in our body
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comment your answers Take Care stous
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thank you so much you have with Biology
