The cyclic process of cell division is called cell cycle, which includes process of cell reproduction and growth.
The cell cycle consists two main phases: interphase and mitotic phase (M-phase).
Interphase: is the longest phase of cell cycle. It consists three stages:
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G1 (Gap-1) phase: It is presynthesis stage, in which cell prepares for DNA replication. Due to which chromosomes are replicated.
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S (synthetic) phase: It is synthetic phase, in which DNA replication takes place.
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G2 (Gap-2) phase: It is post synthetic stage, where cell gets ready for cell division or else we can say for Mitotic phase.
Mitotic phase: at this stage of cell cycle, cell division takes place. It consists five stages:
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Prophase: chromosomes condensed and visible; formation of spindle fibres initiates; breakdown of nuclear membrane.
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Prometaphase: kinetochore microtubules attached to the centromere of the chromosomes (sister chromatids) that are also known as spindle fibres.
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Metaphase: duplicated chromosomes (sister chromatids) arranged at metaphase plate and connected with spindle fibres formed by the pair of centrioles from the poles of the cell.
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Anaphase: with the help of spindle fibres, centromere of each pair of chromosomes migrate towards the pole of the cell i.e. migration of sister chromatids to the opposite direction to each other in the cell. Process of cytokinesis begins.
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Telophase: chromosomes begin invisible, nuclear membrane appears and at the end of cytokinesis in late telophase two daughter cells formed.
