Which phase of the cell cycle is primarily responsible for the regulation of cell division?

• A. G2 phase
• B. G1 phase
• C. S phase
• D. M phase

Answer: (B)

Verified step by step guidance

1. Understand that the cell cycle consists of several phases: G1, S, G2, and M phase, each with distinct roles in cell growth and division.
2. Recall that the G1 phase is primarily responsible for cell growth and preparation for DNA replication, while the S phase is where DNA synthesis occurs.
3. Recognize that the G2 phase involves preparation for mitosis, including the synthesis of proteins needed for cell division.
4. Identify that the M phase (mitosis) is the phase where the actual process of cell division occurs, including chromosome segregation and cytokinesis.
5. Know that the regulation of cell division is tightly controlled at specific checkpoints, especially the G1 checkpoint and the M phase checkpoint, but the M phase is the phase where the cell physically divides, making it primarily responsible for the regulation of cell division.