Learn About Cell Division
2.5 Cell Division
2.5.1 Outline the stages in the cell cycle, including interphase (G1, S, G 2), mitosis and cytokinesis.
2.5.1 Outline the stages in the cell cycle, including interphase (G1, S, G 2), mitosis and cytokinesis (2).
Outline means to give a brief summary
The cell cycle describes the major phases of activity in the division of a cell. The length of the cell cycle depends on the particular function of the cell. For example bacterial cells can divide every 30 minutes under suitable conditions, skin cells divide about every 12 hours on average, liver cells every 2 years, and muscle cells never divide at all after maturing.
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The total length of a cell cycle varies depending on the specialised function of a cell.
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Interphase (grey) is the longest phase which itself occurs in three stages.
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G1 The cell performs its normal differentiated function. Protein synthesis/ mitochondria replication/ chloroplast replication.
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S DNA replication. At this point the mass of DNA in the cell has doubled.
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G2 Preparation for cell division
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Phases of mitosis (see 2.5.4)
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Cytokinesis: division of the cytoplasm to form two daughter cells.
An appreciation of mitosis only comes when you have studied the structure of nucleic acids, DNA replication and some gene expression. At that point you will understand better the significance of the S phase = DNA replication.
Stages of the Cell Cycle