AP BIOLOGY

Detailed explanation-1: -The third part, which asserts that cells come from preexisting cells that have multiplied, was described by Rudolf Virchow in 1858, when he stated omnis cellula e cellula (all cells come from cells).

Detailed explanation-2: -Credit for developing cell theory is usually given to three scientists: Theodor Schwann, Matthias Jakob Schleiden, and Rudolf Virchow. In 1839, Schwann and Schleiden suggested that cells were the basic unit of life. Their theory accepted the first two tenets of modern cell theory (see next section, below).

Detailed explanation-3: -Virchow’s theory stated that just as animals are unable to arise without previously existing animals, cells are unable to arise without previously existing cells. The idea that new cells arose from pre-existing cells in both diseased and healthy tissue was not original.

Detailed explanation-4: -The three tenets of the cell theory are: All living organisms are composed of one or more cells. The cell is the basic unit of structure and organization in organisms. Cells arise from pre-existing cells.

Detailed explanation-5: -As Rudolph Virchow said previously in 1858, omnis cellula e cellula, which is Latin for “all cells arise from other cells."