meiosis questions for biology

Question

Meiosis 

1. After the first Meiotic division, are the daughter cells haploid, diploid, or polyploid?
2. After the second Meiotic division, are the daughter cells haploid or diploid?
3. Which 2 processes in Meiosis are responsible for genetic variation amongst individuals?
4. In which phase of Meiosis do the chromosomes duplicate?

Answer 1

1. After the first meiotic division, the cells are diploid. The originally 2n cells have been replicated and when they divide, they maintain the same amount of DNA so they are still 2n.
2. The end product of meiosis is 4 haploid cells. These cells must be haploid because they are destined to combine with another gamete. If the daughter cells were diploid, there would be too much DNA when the two gametes combine.
3. First, recombination can increase genetic variation. During meiosis, recombination happens during prophase I. Homologous chromosomes (one from each parent) pair gene by gene. Breaks can occur and when they are rejoined, some genetic material is passed to the opposite chromosome. Next, independent assortment also creates genetic diversity. Chromosomes randomly separate to opposite poles during anaphase and each gamete will only have one chromosome. The random odds of each daughter cell being passed on creates variation.
4. DNA is copied during Interphase, in preparation for meiosis.