What is the first stage of mitosis or meiosis called?

The first stage of both mitosis and meiosis is called prophase. During prophase, the chromatin condenses into clearly visible chromosomes, and the nuclear envelope begins to break down. This stage is crucial because it sets the foundation for the subsequent actions that lead to cell division. In prophase, homologous chromosomes (in meiosis) or sister chromatids (in mitosis) become organized and prepare for alignment in the next stage. Additionally, in meiosis, crossing over may occur, where genetic material is exchanged between homologous chromosomes, adding genetic diversity to the resulting gametes. This foundational preparation is vital for ensuring that genetic material is correctly divided between the daughter cells, making prophase a key stage in the overall process of cell division.