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The Nucleus
Figure 5.5 Cancer cells are cells that grow out of control. The normal checks and balances of the cell cycle, which regulate growth and reproduction, are altered. These cells can remain in their original location and form a tumor (a collection of cells) or metastasize. Metastasis is the process by which cancer cells travel through the body, spreading the disease. A diagram of metastasis is shown here.
have relatively high rates of cell division, such as the lining of the gastro-intestinal tract and hair follicles, also are negatively affected. This explains why nausea, vomiting, and hair loss are common side affects with radiation and chemotherapy. CONNECTIONS
The nucleus is the largest cytoplasmic organelle and is surrounded by a double-layered envelope, consisting of inner and outer lipid bilayer membranes. It is considered the “command center� of a cell because its DNA contains the genetic code
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