Word: cytoplasm
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...first published his observations of a common feature he saw in fast-growing tumors: unlike healthy cells, which generate energy by metabolizing sugar in their mitochondria, cancer cells appeared to fuel themselves exclusively through glycolysis, a less-efficient means of creating energy through the fermentation of sugar in the cytoplasm. Warburg believed that this metabolic switch was the primary cause of cancer, a theory that he strove, unsuccessfully, to establish until his death...
...squeezing technique he pioneered to remove the egg's nucleus; the process may have actually left behind enough genetic material for the egg to spontaneously divide. "As the egg starts to mature, [these elements] migrate and after about an hour, you can remove 30% of a primate's egg cytoplasm, for example, and not successfully remove the entire nucleus," says James Byrne, a stem cell postdoctoral fellow at Stanford University who studies parthenogenesis in primates...
...cell be so hard? The cell-cloning technique scientists use offers some clues. Typically, the nucleus of the donor cell, whether fetal or full grown, is transferred to an unfertilized egg from which the nucleus has been removed. In mysterious ways scientists still do not understand, something in the cytoplasm of the egg appears to reset the donor cell's DNA. That resetting, it has been clear from the beginning, works much less reliably when adult cells are used, even when they are relatively immature fibroblast cells...
Grifo's eggs have not yet resulted in any births, but an upside-down version of the procedure has succeeded. At the St. Barnabas Medical Center in Livingston, N.J., Drs. Richard Scott and Jacques Cohen have been taking cytoplasm--the nonnuclear part of a cell--out of young women's eggs and injecting it into the eggs of older women. One egg with refurbished cyotoplasm has grown into babyhood; another birth is expected next spring...
According to Nathan, Sager's research helped to dispel the widely-held belief among scientists that genetic information is only transmitted through genes in the nucleus. In 1963 she published an article showing that genetic information is passed through genes residing on organelles in the cytoplasm as well, he said...