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Author Question: At what point in cell division is a chromosome lost so that, after fertilization (Read 979 times) |
It is believed that the Incas used anesthesia. Evidence supports the theory that shamans chewed cocoa leaves and drilled holes into the heads of patients (letting evil spirits escape), spitting into the wounds they made. The mixture of cocaine, saliva, and resin numbed the site enough to allow hours of drilling.
Cancer has been around as long as humankind, but only in the second half of the twentieth century did the number of cancer cases explode.
Most childhood vaccines are 90–99% effective in preventing disease. Side effects are rarely serious.
Many of the drugs used by neuroscientists are derived from toxic plants and venomous animals (such as snakes, spiders, snails, and puffer fish).
According to the FDA, adverse drug events harmed or killed approximately 1,200,000 people in the United States in the year 2015.