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CELLS, TISSUES, AND SKIN
Figure 5.4 This is a diagrammatic view of the cell cycle. (1) Interphase is a period of cell growth and when a cell carries out its normal functions. (2) The second gap phase (G2) is a relatively brief interval between DNA replication and cell division where a cell completes replication of its centrioles and synthesizes enzymes that control cell division. (3) Chromatin condenses into chromosomes, spindle fibers elongate, and nucleoli and the nuclear envelope disappear during prophase. (4) Some of the spindle fibers attach to chromosomes, causing them to move during prometaphase (also called late prophase). (5) Metaphase is