What happens during the G1 phase of the cell cycle?

During the G1 phase of the cell cycle, the primary activity involves the preparation for DNA replication. This phase follows cell division and is critical for cellular growth and function. During G1, the cell increases in size, synthesizes proteins, produces RNA, and creates the necessary components for DNA synthesis. Additionally, the cell conducts various assessments to ensure that conditions are favorable for DNA replication to occur in the subsequent S phase. This preparation is essential for the orderly progression of the cell cycle, as it allows the cell to gather all resources needed to replicate its DNA accurately.

The other options refer to processes that occur in different phases of the cell cycle. The quiet phase is not an accurate characterization of G1, as it is quite active in terms of growth and preparation. The division into two daughter cells occurs during mitosis, specifically in the M phase. DNA replication itself happens in the S phase, following G1. Thus, the role of G1 is foundational in ensuring that the cell is adequately prepared to enter the next stage of the cycle.