Cell growth control mechanisms and regulation

ELL Cycle Control

Cell Cycle Control

The cell cycle involves a series of events that occur within a cell that results to the division of the cell and its duplication which leads to the production of two daughter cells. For prokaryotic cells-those that do not contain a nucleus the cell cycle occurs through a process known as binary fission. On the other hand for eukaryotic cells-those that contain a nucleus the process occurs in three stages. These are the interphase stage whereby the cell grows, accumulates the nutrients it requires for mitosis in preparation for the cell division and replication of the DNA. The mitotic phase is where the cells begin splitting itself forming tow separate cells and finally the cytokinesis phase whereby the new cell is completely divided.

The cell cycle control mechanism is a crucial process for the survival of the cell. This includes various things such as detecting and repairing of any genetic damage that might occur during the cell cycle. It also helps in preventing any uncontrolled cell division that might take place within the cell. The cell cycle control system of most cells responds to information that it receives back from the processes that it controls. For instance sensors detect whether DNA synthesis is complete, incase there is a malfunction that prevents the process to be successfully competed, signals are conveyed to the control system in order for it to delay the cycle progression to the next stage. The delays provide time for the malfunction to be repaired and also prevent the impending disaster that might occur if the cycle went on prematurely to the next stage (Sunkel, & Pinheiro, 2012).

In most of the cells there are points within the cell cycle that are known as check points at which the cell cycle can be arrested if the events before have not been successfully completed. For instance entry into the mitosis stage can be prevented when DNA replication has not completely occurred. Chromosome separation during mitosis can be delayed if there are some chromosomes that have not been attached to the mitotic spindle properly.

The progression through G1 and G2 is delayed through braking mechanisms incase there is damage of DNA within the chromosome. These delays at the DNA damage checkpoints provide time for the DNA that has been damaged to be repaired. The cell-cycle brakes are then released and the cell cycle resumes.