DNA and division cycle

Before explaining the reproduction process of DNA we must explain about the poin in time where the replication of DNA is carried out during cell division replication of DNA carried out at.

Flow of the cell division

First I will easily expain the of cell divisionprocess.

Even though it is said that the cell repeats division continuously, does not contimously divide.
Period during which cell division occurs which called "Mitotic phase (mitosis)".
Period until the next cell division occurs which called "Interim period".
And they are repeated.
To be more specific,

M period(Mitotic period)→G1 period→S period→G2 period→M period(Mitotic period)

The cell repeats division in this way.。The interphase of a division cycle is means 「G1 period→S period→G2 period」.

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Division of DNA

The replication (synthesis) of DNA happens during the S period. So, S period is called the Synthesis period.
The body multiplies the numver of chromosomes for S period.

In addition, during the G1 period, which is vefore the S period, the body prepares enough nourishment for the reproduction of the new chromosomes.
In addition, that is called the "Period of growth", we can observe the state when a cell gradually grows bigger with a microscope.
At the G1 checkpoint, if there is no damage to the DNA, the body will determine whether there is enough nucleotides to replicate the chromosome.
For this reason it is also referred to as the "preparation stage" synthetic.

The role of the G2 phase is to prepare for cell division. In the S phase, the cell is synthesized and the microtubule undergoes preparation for the next cell division.
At the G2 checkpoint along with it, the body system has to check whether the cells can enter the M period.

Finally, cell division occurs during the M period.

In this way, the period of time of cell division and DNA replication are adjusted well to progress at the same time.
Their role is related to each other.
However, this is the case of eukaryotic cells. In the case of prokaryotic cells that make up the body of prokaryotes, it'll be a little different.
In prokaryotic cells the DNA is constantly being replicated.

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