If 2n = 10, how many homologous chromosomes are in each cell at the beginning of prophase ii of meiosis?

Meiosis occurs in two phases. Since the first phase is the reductive one, before prophase ii, there are 5 homologous chromosomes in each cell.

Through Meiosis, a diploid cell (2n) produces four haploid daughter cells (n).

After DNA replication there are two meiotic phases.

The first one is a reductive phase, in which homologous chromosomes separate. In the second phase, the cell suffers a new, not reductive division.

1. In the first phase, Meiosis I:

Prophase I: Chromosomes condensate and become visible. Occurs crossing-over between homologous chromosomes. Crossin-over makes the daughter cells to be genetically different from the original one.Metaphase I: Homologous chromosomes randomly align in the equatorial plane. Anaphase I: In this phase occurs the division and independent separation of homologous pairs. Each chromosome migrates to different poles. This separation generates different chromosomal combinations in the daughter cells.Telophase I: Chromosomes of homologous pairs are already in the corresponding poles, and the nuclear membrane forms again in each pole.

2. In the second phase, Meiosis II:

Prophase II: Chromosomes condensate again and become visible.Metaphase II: Chromosomes join the spindle apparatus and migrate to the equatorial plane, where they randomly line up. Sister chromatids are holden together until they reach the Anaphase.Anaphase II: Centromeres divide, chromatids get separated, and each of them goes forward an opposite cellular pole.Telophase II: Once in the poles, the chromosomes become lax again, and the nuclear membrane forms again.

Cytokinesis occurs.

Since the first phase is the reductive one, before prophase ii, there are 5 homologous chromosomes in each cell. The genetic material was divided during the first phase.

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The answer is 5. Meiosis I reduces the ploidy of a cell by half.Therefore, if a cell was diploid (2n), then at the end of meiosis I, the two formed daughter cells will have haploid (n) number of chromosomes. Meiosis II is similar to mitosis and does not reduce ploidy.

(2n)/2= 10/2; n = 5

Bruh i don’t know the answer tbh but you can google it