Where do the most significant differences between meiosis and mitosis occur?

The most significant differences between meiosis and mitosis occur during Prophase I. This phase is critical in meiosis because it includes a process called synapsis, where homologous chromosomes pair up and undergo genetic recombination or crossing over. This exchange of genetic material between homologous chromosomes increases genetic variability among gametes, which is one of the main purposes of meiosis.

In contrast, mitosis focuses on the division of somatic cells, producing two genetically identical daughter cells. There is no pairing of homologous chromosomes or crossing over in mitosis, highlighting a significant difference in how the two processes contribute to genetic diversity.

The importance of Prophase I is further underscored by the fact that it sets the stage for the further stages of meiosis, ultimately leading to the formation of four unique gametes, a crucial aspect of sexual reproduction.