The Impact of Growth Factors on Cell Cycle Progression

What is the phase during which growth factors affect the cell cycle and link cell division to cell growth and nutrition?

a) G1 Checkpoint
b) G2 Checkpoint
c) M Checkpoint
d) S Checkpoint
Final answer:

The Impact of Growth Factors on Cell Cycle Progression

The G1 checkpoint is the phase where growth factors influence the cell cycle, linking cell division to growth and nutrition, and it is the main point where external forces affect cell-cycle progression.

During the cell cycle, various checkpoints play crucial roles in ensuring proper cell division and growth. One of the key checkpoints is the G1 checkpoint, which evaluates whether the cell is ready to divide and has enough nutrients to support the process.

At the G1 checkpoint, growth factors exert a significant influence on the cell by determining whether conditions are favorable for cell division. These growth factors can promote or inhibit cell-cycle progression based on factors such as cell size, nutrient availability, and the absence of DNA damage.

When growth factors signal that conditions are suitable for division, the cell proceeds to the next phase of the cell cycle. However, if unfavorable conditions are detected, the cell may enter a resting state known as Go until the environment becomes more conducive for division.

Overall, the G1 checkpoint serves as a critical juncture where external signals, particularly growth factors, regulate the progression of the cell cycle and ensure that cell division is coordinated with cell growth and nutrition.