Answer:
Dutch scientist Anton van Leeuwenhoek (AHN-tohn vahn LAY-ven-hook) (1632-1723) made important contributions in the development of the microscope. Using a microscope he made by hand he observed bacteria, small blood vessels, and muscle fibers. He once said, "No more pleasant sight has met my eye than this of so many thousands of living creatures in one small drop of water." Leeuwenhoek's work helped establish the study of cell biology.
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