Word: celling
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Dates: during 1980-1989
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Scientists have long believed that at the genetic level, men and women are pretty much the same. According to textbooks, only two of the 46 gene-carrying chromosomes in a human cell -- a pair known as the sex chromosomes -- are noticeably different in males and females. But at a genetics seminar last week at Jackson Laboratory in Bar Harbor, Me., this conventional wisdom took a beating. Participants cited evidence that there may be many more differences in male and female genes than previously thought. That revelation challenges assumptions about heredity held for more than a century...
Human chromosomes come in 23 pairs. One member of each pair is from a person's mother and the other from the father. Except for the two sex chromosomes, the members of each pair were thought to be interchangeable. It seemed that the way a chromosome functioned in the cell had nothing to do with whether it came from the mother or the father...
Laboratory experiments have shown that electric and magnetic fields can exert an influence on biological processes. Cells naturally maintain an electric charge across their membranes that is essential to the normal functioning of human tissues. In cell cultures, exposure to electromagnetic fields can affect the flow of chemicals across membranes, interfere with synthesis of genetic material, alter the activity of hormones and other chemicals, and change the behavior of cancer cells. Studies with mice show disruptions in eating, breathing and sleeping patterns. An experiment with human volunteers who were exposed to electromagnetic fields found they experienced a reduced heart rate...
...term exposure to the sun, especially between 10 a.m. and 3 p.m., weakens the skin's elasticity and brings on premature wrinkling and sagging. Of greater concern, it causes as many as half a million new cases of skin cancer every year. Most of these are basal or squamous cell carcinomas, which have high cure rates. But solar radiation may be a cause of melanoma, which can be fatal. Ultraviolet light apparently weakens the immune system; after a severe sunburn, some people suffer outbreaks of oral herpes or other disorders. Excessive exposure aggravates cases of chicken...
Instead of using the conventional technique of painstakingly inserting / foreign genes into an egg cell with a tiny needle, the scientists simply bathed sperm cells in a solution of bacterial DNA. The sperm, from mice, incorporated the genes by some still unknown process, then went on to fertilize eggs in a test tube. As the mice matured, 30% of them produced an enzyme normally made only by bacteria -- proof that the bacterial DNA had become part of the mice's genetic makeup...