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    The Cell Cycle

    Biology

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      • Introduction to the Cell Cycle
      • Components of the Cell Cycle
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    Terms

    Terms
    • Cell Cycle

      The two-phase cycle during which a cell replicates its DNA, divides, and then goes through the processes necessary to replicate DNA, etc. Cell cycles can vary in duration from 8 minutes to 1 year, though the general duration is around 24 hours for fast-dividing mammal cells. The two phases of the cell cycle are interphase and mitosis.

    • Cyclin-dependent protein kinase

      A protein found in eukaryotic cells responsible for regulating progression through the cell cycle. Must be complexed with cyclins in order to be active.

    • Cyclin

      A protein found in eukaryotic cells that continually goes through cycles of synthesis and degradation during the cell cycle. When synthesizes, cyclins activate cyclin-dependent protein kinases. Cyclins are synthesized or degraded according to the cells readiness to move into the next stage of the cell cycle.

    • G0

      A sub-phase of G1. Cells in G1 that are not ready to progress in the cell cycle enter G0 for extended periods of time until they are ready to proceed. G0 can vary in length from minutes to years.

    • G1

      The first part of interphase, between the end of mitosis and the beginning of S phase. A period in which cells grow and make preparations for DNA replication in S phase.

    • G2

      The final part of interphase, between the end of S phase and the beginning of mitosis. G2 is an intermediate phase during which cells make certain they are ready to enter into mitosis.

    • Interphase

      The longer of the two phases of the eukaryotic cell cycle that includes the sub-phases G1, S phase, and G2. Mitosis is the second phase of the cell cycle.

    • Mitosis

      The shorter phase of the two-phase eukaryotic cell cycle; cells divide during mitosis. Interphase is the second phase of the cell cycle.

    • S phase

      The second, middle part of interphase, occurring between G1 and G2; during S phase DNA is duplicated before cell division.

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