The number of chromosomes in the somatic cell of Drosophila is 8. Determine the number of chromosomes and DNA
The number of chromosomes in the somatic cell of Drosophila is 8. Determine the number of chromosomes and DNA molecules in Drosophila during ovogenesis in anaphase meiosis 1 and prophase meiosis 2. Explain the results.
In somatic cells, a diploid set of chromosomes – 8 chromosomes, 8 DNA molecules.
During ovogenesis in the anaphase of meiosis I – 8 chromosomes 16 chromatids. In interphase, DNA replication (the number of DNA molecules becomes twice as many). Next, I division of meiosis is reduction, the number of chromosomes and DNA molecules at each pole of the cell in anaphase I will be half as much (homologous chromosomes diverge to the poles of the cell).
During ovogenesis in prophase II – 4 chromosomes, 8 DNA molecules. In telophase I, two haploid cells are formed, two-chromatid chromosomes (1n2c). After reduction division, DNA replication does not occur; the number of chromosomes and DNA molecules remains the same (1n2c) as in telophase I. That is, in prophase II, the set 1n2c.
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