Answer:
C. transition points during the cell cycle that ensure all cellular components are functioning properly
Explanation:
Cell cycle is the series of events that occurs from the preparation of the cell for division to the actual division. Prior to this division, certain processes need to occur to ascertain that each daughter cell receives the correct number of chromosomes and that mistakes that can change the composition of the genetic material does not occur. With respect to this, the cell ensures that a cell with anomalies does not continue the division process in a control mechanism called CHECKPOINT.
Checkpoint is that transition point in which the progress of each stage of the cell cycle is monitored and corrected before proceeding. Checkpoints occur at the end of G1, G2 and Metaphase stages. In G1 checkpoint, the cell ensures all cells meet the requirements for their genetic material to be replicated in S-phase. If they do, they proceed. If some don't, the process may be paused till conditions are met.
In the transition from G2 and M phase, checkpoints are done to ascertain that all DNA in each cell has been replicated without errors.
In the Metaphase stage, checkpoints occurs to ensure that all sister chromatids are attached to spindle microtubules at their kinetochore in order to facilitate separation in the anaphase stage.
