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There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Sperm cells are so tiny that 400 to 500 million (400,000,000–500,000,000) of them fit onto 1 tsp.
More than 34,000 trademarked medication names and more than 10,000 generic medication names are in use in the United States.
More than 150,000 Americans killed by cardiovascular disease are younger than the age of 65 years.
Bacteria have flourished on the earth for over three billion years. They were the first life forms on the planet.
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