In which stage of mitosis do chromosomes condense and the nucleolus disappears?

During prophase, the first stage of mitosis, several critical events occur that set the stage for successful cell division. One of the most notable changes is the condensation of chromatin into distinct chromosomes, making them visible under a microscope. Each chromosome consists of two sister chromatids joined at a centromere, which is crucial for the proper segregation of genetic material later on.

In addition to chromosomal condensation, the nucleolus, which is the region within the nucleus responsible for ribosomal RNA synthesis, begins to disappear during prophase. This disappearance signifies that the cell is preparing to reorganize its nucleus in order to divide. The breakdown of the nuclear envelope typically follows, allowing the spindle apparatus to interact with the chromosomes, which is essential for their movement during the later stages of mitosis.

Overall, prophase is characterized by these significant morphological and structural changes, highlighting its importance in the mitotic process.