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Phases and Events of the Cell Cycle

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2.0 DISCUSSION
2.1 Phases And Events Of The Cell Cycle
2.1.1 Phases And Subphases
Generally, there are two phases in cell cycle. Those are interphase and mitotic phase.

Figure 1.0: The cell cycle
Interphase consist of G1, S, and G2. The name of G actually represent as “gap” while S represent as “synthesis”. So, the name for G1 is also known as “first gap”, S is “synthesis”, and G2 is “second gap”. There is a reason why it is called “gap”. It is because, when the cells were observed long time ago, it appeared as inactive which in inactive period, it create a gap between S phase and mitotic phase. However, as the world hurtles down the path of fast scientific development, we now know that there is a growth and metabolic activity inside cells.
The mitotic phase is divided into two, mitosis and cytokinesis. Mitosis consist of prophase, prometaphase, metaphase, telophase, and anaphase.
2.1.2 Duration Of Cell Cycle Approximately, G1 takes about 5 – 6 hours, S takes about 10 – 12 hours, and G2 takes about 4 – 6 hours. Mitotic phase takes less than 1 hour. Overall, a normal human cells take about 24 hours to complete a cell cycle.
2.1.3 Events In The Cell Cycle In each subphases, several events occurred in well ordered. Starting from G1, the growth of cells occurred in this phase by producing proteins and cytoplasmic organelles. Until at the end of G1, the enzymes required for DNA synthesis become more active. The process continue with S phase, in this entire phase, the chromosome starts to duplicate and replicates forming two sister chromatids. Same as other organelles, involving in replication as well. The last phase, G2, the cells proceed the growth and the synthesization of protein keep increasing as it completes the preparation to be divided.

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