Final answer:
The G1-S Checkpoint evaluates cell size, nutrient availability, DNA integrity, and the influence of cell signaling and growth factors to determine if a cell should proceed to the S phase of cell division.
Step-by-step explanation:
The G1-S Checkpoint is critical in determining whether a cell is ready to proceed with the cell division process. Specifically, this checkpoint assesses:
- Cell Size: The checkpoint evaluates whether the cell is large enough to divide.
- Nutrient Availability: Sufficient nutrients must be available for the cell to progress.
- DNA Integrity: The checkpoint examines the DNA for any damage that might hinder replication.
- Cell Signaling and Growth Factors: These external factors influence the cell to move past the checkpoint.
A cell that does not satisfy these criteria will not be permitted to enter the S phase, where DNA replication occurs. If there are issues, the cell may enter a resting state, Go, or attempt to resolve the problematic condition before moving forward.