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In 1664, English scientist Robert Hooke viewed a thin slice of cork through an early microscope. Cork looked to him as if it were constructed of dozens of tiny rectangular compartments.
He called them cells, from the Latin word cella, meaning “small room.”
At first, scientists couldn’t see much within a cell and thought it was just filled with jelly. They called that jelly protoplasm. But improved microscopes slowly changed that view. We know now that each cell is really a complex part of life.
