Exploring Cell Cycle Checkpoints

The video explains how the cell cycle is controlled through various checkpoints: G2 checks DNA replication, the mitosis checkpoint ensures spindle alignment, and G1 checks for DNA damage. Apoptosis can occur if issues are detected. Cyclin and CDK regulate the cycle, influenced by external signals like growth factors and internal signals. The G0 state is a resting phase where cells do not divide.

What is the primary function of the G2 checkpoint?

• To check if DNA is damaged

• To ensure DNA replication occurred correctly

• To align spindles with chromosomes

• To initiate apoptosis

During which phase does the mitosis checkpoint occur?

• G1 phase

• S phase

• M phase

• G2 phase

What does the mitosis checkpoint verify?

• If the cell is ready for apoptosis

• If DNA is replicated

• If DNA is damaged

• If spindles are aligned correctly with chromosomes

What is checked during the G1 checkpoint?

• Cell size

• DNA damage

• Spindle alignment

• DNA replication

What is apoptosis?

• DNA replication

• Programmed cell death

• Spindle formation

• Cell growth

What role do cyclins play in the cell cycle?

• They initiate apoptosis

• They form spindles

• They regulate cell cycle checkpoints

• They repair DNA

Which external signal can influence the cell cycle?

• Cyclins

• Growth factors

• DNA damage

• Spindle alignment

What is the function of MPF (mitosis promoting factor)?

• To initiate apoptosis

• To align spindles

• To add phosphates to proteins

• To repair DNA

What is the most important checkpoint in the cell cycle?

• G0 checkpoint

• G2 checkpoint

• G1 checkpoint

• Mitosis checkpoint

What is the G0 state?

• A state where the cell undergoes apoptosis

• A phase where the cell is actively dividing

• A phase where the cell is preparing for mitosis

• A state where the cell is not dividing and is inactive