you start with a cell that has a 2N number of 84. this cell goes through meiosis. for each of the following stages, determine the number of chromosomes, chromatids, and bivalents present a single cell.

a. Prophase I
b. Anaphase I
c. Metaphase II
d. Cytokinesis II

I think if you look through some of the images at the following link, it will answer these questions.

http://images.google.com/images?&hl=en&num=10&btnG=Google+Search&lr=&as_ft=i&as_qdr=all&as_dt=i&as_rights=&safe=images&ie=UTF-8&oe=UTF-8&um=1&sa=N&tab=wi&q=meiosis

thanks =]

To determine the number of chromosomes, chromatids, and bivalents present in a single cell at different stages of meiosis, you can follow these general guidelines:

a. Prophase I:
- In prophase I, the chromosomes condense and pair up to form bivalents.
- Each bivalent consists of two homologous chromosomes, which means that the number of chromosomes remains the same, 2N.
- However, each chromosome consists of two identical sister chromatids, resulting in a total of 4 chromatids per bivalent.

b. Anaphase I:
- In anaphase I, the homologous chromosomes separate and move to opposite poles of the cell.
- As a result, the number of chromosomes reduces to N, as each homologous chromosome separates from its pair.
- Each chromosome still consists of two sister chromatids, so the number of chromatids remains 2N.

c. Metaphase II:
- In metaphase II, the chromosomes align on the metaphase plate, and the spindle fibers attach to the kinetochores of the sister chromatids.
- The number of chromosomes remains the same as in anaphase I, N. Each chromosome consists of two sister chromatids, so there are 2N chromatids in total.

d. Cytokinesis II:
- Cytokinesis II is the final stage of meiosis, where the two daughter cells divide into four haploid cells called gametes.
- The number of chromosomes in each gamete remains N.
- Since cytokinesis II completes the separation of sister chromatids, each gamete contains only one chromatid per chromosome, resulting in N chromatids.

Please note that the specific numbers provided in your initial question, such as 2N = 84, are not necessary to determine the answers. If you have a different value for 2N, you can still apply the above guidelines to calculate the number of chromosomes, chromatids, and bivalents at each meiotic stage.