during what stage of the cell cycle does replication occur?
During what stage of the cell cycle does replication occur?
Answer: DNA replication occurs during the S (Synthesis) phase of the cell cycle. The cell cycle is divided into several distinct phases that ensure proper cell growth, DNA replication, and cell division. These phases include:
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G1 Phase (Gap 1): This is the first phase after cell division, where the cell grows and performs its normal functions. During this phase, the cell increases in size and prepares the necessary components for DNA replication.
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S Phase (Synthesis): This is the phase where DNA replication occurs. Each chromosome is duplicated to ensure that both daughter cells will receive an identical set of chromosomes. The replication process involves the unwinding of the DNA double helix and the synthesis of a new complementary strand for each original strand.
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G2 Phase (Gap 2): Following the S phase, the cell continues to grow and prepares for mitosis. During this phase, the cell checks for any DNA damage that may have occurred during replication and makes necessary repairs.
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M Phase (Mitosis): This is the phase where the cell divides. Mitosis is further divided into sub-phases: prophase, metaphase, anaphase, and telophase. The replicated chromosomes are separated into two new nuclei, followed by cytokinesis, which divides the cytoplasm, resulting in two daughter cells.
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G0 Phase: Some cells enter this phase, which is a resting state where the cell is not actively preparing to divide. Cells can remain in G0 for extended periods, depending on the type of cell and external conditions.
In summary, DNA replication specifically occurs during the S phase of the cell cycle, ensuring that each daughter cell will have an identical set of genetic information.