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Author Question: The Ming Dynasty ships used magnetic compasses similar to those used today. (Read 58 times) |
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The familiar sounds of your heart are made by the heart's valves as they open and close.
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The average office desk has 400 times more bacteria on it than a toilet.
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Interferon was scarce and expensive until 1980, when the interferon gene was inserted into bacteria using recombinant DNA technology, allowing for mass cultivation and purification from bacterial cultures.
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The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
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More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.