How long does the mitosis (M) phase typically last?

The mitosis (M) phase of the cell cycle is typically known for being a relatively brief period compared to the other phases, such as interphase, which can take much longer. In a typical human cell, the M phase generally lasts about 1 hour. This phase includes the processes of prophase, metaphase, anaphase, and telophase, followed quickly by cytokinesis, where the cell divides into two daughter cells.

The rapid nature of the M phase is critical for maintaining efficient cell division and ensuring that genetic material is accurately replicated and distributed to each new cell. Understanding the length of this phase is vital in fields like oncology, where the timing of cell division can impact the effectiveness of chemotherapy, which often targets rapidly dividing cells.

In contrast, the other given time periods—20 hours, 18 hours, and 10 hours—are much longer than what is typically observed for the M phase, as they would more accurately represent the entire interphase duration rather than just the mitosis itself.