| Medicine |
Q: We have had chlorinated public water systems since the early 20th century—enough time for Cryptosporidium or Clostridium perfringens to develop metabolic or behavioral changes to survive chlorination. Why don't microorganisims become resistant to chlorine?
A: To date, no microorganism has developed resistance to the chlorine used in commercial water supplies since the chlorine kills the organism before it can develop resistance.
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| Bioscience |
Q: Why do you feel tired after eating turkey?
A: The popular answer is that turkey contains lots of tryptophan, which raises brain serotonin levels, which makes you sleepy. However, this is not strictly correct.
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| Bioscience |
Q: Does "handedness" exist among other animals? What evolutionary advantages arise from handedness in humans (and why does right-handedness seem to predominate)?
A: Yes, there are analogs to human handedness in animals, across taxonomic classes, and varied in strength and expression. Does handedness confer an evolutionary advantage in humans? Most likely, but a conclusive answer is surprisingly difficult to come by.
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