Question

7.
What are the 3 checkpoints normal cells go through to prevent unregulated cell division?

Answer 1

Answer:

The three cell cycle checkpoints are:

1. G1 Checkpoint
2. G2 Checkpoint
3. Spindle Checkpoint

Explanation:

Cell Cycle Checkpoints:

Cell cycle checkpoints are regulatory points at which the current state of the cell is assessed to determine whether the cell cycle can continue or not.

• The G1 checkpoint confirms the cells entry into the mitotic phase; it commits the cells for division. If a cell passes G1 checkpoint, it will continue in the cell cycle until it divides into two daughter cells. This checkpoint checks DNA damage, the presence of adequate nutrients and suitable cell size.
• The G2 checkpoint operates at the G2/M transition. It checks DNA damage and assesses whether DNA has completely and successfully replicated during the S-phase. If DNA damage is detected, DNA repair mechanisms are activated.
• The spindle checkpoint assesses whether all chromatids have successfully attached to the spindle fibers. This is a crucial checkpoint as the integrity of cell division depends on the correct number of chromosomes received by each daughter cell.