Select all that apply Which of the following are processes within meiosis that produce genetic variation in offspring? prophase II metaphase I crossing-over during prophase I cleavage and cytokinesis telophase II
The Correct Answer and Explanation is:
Correct Answers:
✔️ Metaphase I
✔️ Crossing-over during Prophase I
Explanation:
Genetic variation in offspring is a crucial outcome of meiosis, the type of cell division responsible for producing gametes (sperm and egg cells). Two major processes within meiosis create genetic variation: crossing-over during Prophase I and independent assortment during Metaphase I.
Crossing-over during Prophase I occurs when homologous chromosomes pair up and exchange segments of genetic material. This process results in new combinations of alleles along each chromosome, meaning that the chromosomes inherited from parents are shuffled. As a result, each gamete contains unique genetic information.
Metaphase I contributes to genetic variation through a process called independent assortment. During this stage, homologous chromosome pairs align randomly at the metaphase plate. The way these pairs line up determines how the chromosomes will be distributed into daughter cells. This randomness ensures that each gamete has a different combination of maternal and paternal chromosomes, greatly increasing genetic diversity.
The other stages listed in the question do not directly contribute to genetic variation:
- Prophase II: This is part of the second meiotic division, but it does not involve crossing-over or genetic reshuffling.
- Cleavage and cytokinesis: These processes involve the physical division of the cell but do not alter the genetic content of the chromosomes.
- Telophase II: This marks the end of meiosis when nuclei reform around the haploid chromosome sets, but again, it does not create new genetic variation.
In conclusion, the key events responsible for producing genetic variation during meiosis are crossing-over during Prophase I and independent assortment during Metaphase I, both of which ensure that offspring inherit unique genetic combinations from their parents.
