The Phases of the Cell Cycle

Through this phase, the cells are ready for the DNA replication process. In order for DNA to replicate it is necessary to judge whether it can proceed to S phase through G1 phase. If the cell is not ready enough to support DNA replication, there is a period called G 0 near the middle of the G 1 phase and the cells can continue to grow and then enter the G 1 phase to complete the process, Go to S phase of the period. SparkNotes will continue to grow even as cells enter S phase.

When replicating chromosomally packaged DNA, S phase or synthesis is the phase of the cell cycle. This phenomenon is an important aspect of the cell cycle as replication allows each cell produced by cell division to have the same genetic makeup. (The details of how this replication is done is contained in the DNA replication SparkNote of the SparkNotes series specialized in molecular biology.) Many events other than chromosomal replication occurred during the S phase It was. Cell proliferation continues throughout the S phase at the same rate as the synthesis of many proteins and enzymes involved in DNA synthesis. After DNA replication is complete, the cells contain twice as many normal chromosomes and are ready to enter the stage called G2.

Cell cycle analysis is a method in cell biology that uses flow cytometry to distinguish cells at different stages of the cell cycle. Prior to analysis, cells were permeabilized, treated with fluorescent dye and the fluorescent dye quantitatively stained DNA, typically propidium iodide (PI). Therefore, the fluorescence intensity of cells stained at a particular wavelength is related to the amount of DNA they contain. Since the cellular DNA content is replicated in the S phase of the cell cycle, G 0 phase and G 1 phase (before S phase), S phase, G 2 phase and M phase (S The relative number of cells can be determined. Fluorescence is twice that of G0 / G1 phase cells. Abnormal cell cycle is a symptom of various cell injuries such as DNA damage, and cells may interrupt cell cycle at certain checkpoints to prevent conversion to cancer cells (carcinogenicity).

Interphase is the stage of the cell cycle in which the majority of typical cell longevity lies. At this stage, the cells duplicate DNA in preparation for mitosis. Interphase is the "daily life" or metabolic stage of cells that cells acquire nutrients, metabolize them, grow, read their DNA, and perform other "normal" cellular functions. Most eukaryotic cells are in most cases in an interim period. This stage was formerly known as the resting stage. However, the interval is not just a cell that is still, but the cell is alive and ready for the next cell division, so its name will change. A common misunderstanding is that this interval is the first stage of mitosis. However, since mitosis is nuclear division, the initial stage is actually the first stage.