There are traditionally six, basic, simple machines; the pulley, the inclined plane, the lever, and the wheel/axle are four of them. What are the other two ?
Troy weight is used to measure gold and silver and precious stones. (Other things are usually measured using the metric or avoirdupois systems.) How many ounces are there in a Troy pound. ?
In 1991 William Fenical, a chemist at the Scripps Institution of Oceanography in San Diego, went to the Philippines to hunt for organisms that might provide medically useful compounds. He found a two pound mass of Diazona chinensis in a cave 100 feet below the ocean surface. Back in San Diego he isolated, from its tissue, a chemical that killed colon cancer cells in laboratory tests.
- Is Diazona chinensis a plant or an animal? And, to what taxonomic group of organisms does it belong?
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