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Section 10-1: Cell Growth
The larger a cell becomes, the more demands the cell places on its DNA and the more trouble the cell has moving enough nutrients and wastes across the cell membrane.
Section 10-2: Cell Division
During the cell cycle, a cell grows, prepares for division, and divides to form two daughter cells, each of which then begins the cycle again.
Biologists divide the events of mitosis into four phases: prophase, metaphase, anaphase, and telophase.
During prophase in animal cells, the centrioles separate and take up positions on opposite sides of the nucleus.
During metaphase, the chromosomes line up across the center of the cell. Microtubules connect the centromere of each chromosome to the poles of the spindle.
During anaphase, the centromeres that join the sister chromatids split, allowing the sister chromatids to separate and become individual chromosomes.
In telophase, the chromosomes, which were distinct and condensed, begin to disperse into a tangle of dense material.
Cytokinesis is the division of the cytoplasm.
Section 10-3: Regulating the Cell Cycle
Cyclins regulate the timing of the cell cycle in eukaryotic cells.
Cancer cells do not respond to the signals that regulate the growth of most cells. As a result, they form masses of cells called tumors that can damage the surrounding tissues.