Why is g2 phase important

Interphase : Interphase, which appears to the eye to be a resting stage between cell divisions, is actually a period of diverse activities. Those interphase activities are indispensible in making the next mitosis possible. Interphase generally lasts at least 12 to 24 hours in mammalian tissue.

During this period, the cell is constantly synthesizing RNA, producing protein and growing in size. By studying molecular events in cells, scientists have determined that interphase can be divided into 4 steps: Gap 0 G0 , Gap 1 G1 , S synthesis phase, Gap 2 G2.

Gap 0 G0 : There are times when a cell will leave the cycle and quit dividing. This may be a temporary resting period or more permanent. An example of the latter is a cell that has reached an end stage of development and will no longer divide e. Cell division through mitosis is an asexual form of cell multiplication that is used to produce more of the same kind of cell.

Higher animal cells use mitosis to produce new cells include cells that wear out quickly such as skin cells. The process is also used during tissue growth such as in young animals or to repair damage. In some tissues, once an organism has the required number of cells of a particular type, no new cells are needed, and the existing cells enter the G0 phase where they no longer multiply.

This is especially true of highly differentiated cells such as nerve cells. Once the brain or the spinal cord has the right number of cells, the nerve cells don't divide to produce more. The G1 Gap Phase. This is the gap between cell division and DNA replication. The cell gets ready for its next division in the cell cycle or it exits the cell cycle and enters G0. The S Synthesis Phase. The cell is committed to starting the next cell division and makes copies of its DNA while synthesizing additional proteins required for cell division.

This is the gap between DNA replication and mitosis. The cell reproduces its organelles and makes sure everything is ready for the split.

After cell growth during the G1 phase and DNA replication during the S phase, the cell is ready to enter the G2 phase. G2 is called a gap phase because no further cell division-specific progress takes place. Instead there are high levels of preparation and checking to make sure everything is in place for a successful mitosis. Before the G2 phase can start, each chromosome of the cell must have been duplicated, and the proteins required for the extra cell membranes and cell structures must be present.

At the beginning of G2, the organelles such as the mitochondria and the lysosomes start multiplying. These organelles have their own DNA and can start dividing independently, but the cell itself has to create extra ribosomes to satisfy the needs of the prospective two daughter cells.

First, the cell has to check that everything is ready for mitosis, and it has to correct any deficiencies. If the cell detects major problems that can't be fixed immediately, it may interrupt the cell cycle and stop the process of division.

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