Askjagden's Guide to Biology: Regulation of the Cell Cycle
The cell cycle is regulated. Everything in growth and division is perfectly timed. How is it regulated? Scientists realized that there is a protein that regulates it. That protein is now called cyclin, and it regulates the timing of the cell cycle in eukaryotic cells.
Here's how it works: scientists put a sample of the cytoplasm of a cell going through mitosis into another cell in interphase. The other cell immediately entered mitosis.
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