Max Schultze

Max Schultze (born March 25, 1825, Freiburg, Germany—died January 16, 1874, Bonn) was a German zoologist and cytologist who, in 1861, defined the cell as a mass of protoplasm with a nucleus and recognized the protoplasm, a living substance, as the fundamental unit of life in both plants and animals, proposing that the cell need not be enclosed by a wall—a concept that helped establish the modern version of cell theory.