During spermatogenesis,
why is the chromosome no of 4 daughter cells produced by the meiotic division of secondary spermatocyte is same as that of secondary spermatocyte.
since during meiosis, chromosome no reduces to half.
During spermatogenesis,
why is the chromosome no of 4 daughter cells produced by the meiotic division of secondary spermatocyte is same as that of secondary spermatocyte.
since during meiosis, chromosome no reduces to half.
Meiosis comprises of 2 divisions Meiosis I and Meiosis II. In the first division crossing over, recombination takes place and chromosome number is reduced to half. Even though after the first meiotic division, number of chromosomes is 46 but the number of centromere is 23, each centromere attaches 2 homologous chromosomes, so we call it a reductional division. So, after Meiosis I, 2 cells are formed with 46 chromosomes but 23 centromeres each. In Meiosis II, no crossing over or recombination takes place, it is just like mitosis. The centromere divides in the Anaphase II and each cell gets 23 chromosomes and the number of centromere is also 23 in each cell. In meiosis II those 2 cells produced after meiosis I divide to form 4 cells with 23 chromosomes and 23 centromeres each.
Since the number of centromeres is the same in secondary spermatocytes and spermatids we say that the number is n.
Meiosis comprises of 2 divisions Meiosis I and Meiosis II. In the first division crossing over, recombination takes place and chromosome number is reduced to half. Even though after the first meiotic division, number of chromosomes is 46 but the number of centromere is 23, each centromere attaches 2 homologous chromosomes, so we call it a reductional division. So, after Meiosis I, 2 cells are formed with 46 chromosomes but 23 centromeres each. In Meiosis II, no crossing over or recombination takes place, it is just like mitosis. The centromere divides in the Anaphase II and each cell gets 23 chromosomes and the number of centromere is also 23 in each cell. In meiosis II those 2 cells produced after meiosis I divide to form 4 cells with 23 chromosomes and 23 centromeres each.
Since the number of centromeres is the same in secondary spermatocytes and spermatids we say that the number is n.
