AP Bio Insta-Review Topic 4.7*: Regulation of Cell Cycle

Front

What is the role of the M checkpoint in the cell cycle?

Back

The M checkpoint ensures that all chromosomes are properly attached to the spindle apparatus before the cell proceeds to anaphase, preventing nondisjunction.

Front

What does the G1 checkpoint assess?

Back

The G1 checkpoint assesses whether the cell is ready to divide, checking for DNA damage and sufficient resources.

Front

In which phase of the cell cycle does the G2 checkpoint occur?

Back

The G2 checkpoint occurs after DNA replication and before mitosis, ensuring that DNA is undamaged and fully replicated.

Front

What is cyclin and its role in the cell cycle?

Back

Cyclin is a regulatory protein whose levels fluctuate throughout the cell cycle, activating cyclin-dependent kinases (CdKs) to drive the cell cycle forward.

Front

What happens to cyclin levels during the cell cycle?

Back

Cyclin levels increase and decrease at specific points in the cell cycle, particularly rising before mitosis and falling after.

Front

What is the function of cyclin-dependent kinases (CdKs)?

Back

CdKs are enzymes that, when activated by binding to cyclins, phosphorylate target proteins to regulate the cell cycle.

Front

What is the significance of the G2 checkpoint?

Back

The G2 checkpoint is crucial for ensuring that the cell is ready to enter mitosis, preventing errors in cell division.

Front

What can happen if the M checkpoint fails?

Back

If the M checkpoint fails, it can lead to nondisjunction, resulting in cells with an abnormal number of chromosomes.

Front

What is the relationship between cyclin and CdK levels during the cell cycle?

Back

Cyclin levels vary, increasing to activate CdKs, while CdK levels remain relatively constant throughout the cycle.

Front

What triggers the transition from G2 to M phase?

Back

The transition from G2 to M phase is triggered by the accumulation of cyclin that binds to CdKs, activating them.