Schleiden and Schwann

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The forerunner of the concept of TOTIPOTENCY was the cell theory which was postulated by SCHLEIDEN in 1838 with respect to plants and by SCHWANN in 1839 with respect to plants and animals. Essentially this theory purports that the cells of an organism are discreet relatively autonomous entities. The fact that SCHWANN recognised that cells of an organism possessed an independent life and were yet still part of and dependent on the whole multicellular structure is clearly evident in his words of 1839:

"One can thus construct the following two hypotheses concerning the origin of organic phenomena such as growth: either this origin is a function of the organism as a whole, or growth does not take place by means of any force residing in the entire organism but each elementary part possesses an individual force, a separate life. Among the lower plants any cell can be separated from the plant and continue to grow. Thus, entire plants may consist of cells whose capacity for independent life can be clearly demonstrated..... That not every cell, when separated from the organism, does in fact grow is no more an argument against this theory than is the fact that a bee soon dies when separated from the swarm a valid argument against the individual life of a bee."

Thus both Schleiden and Schwann promulgated the notion that cells of an organism were essentially alike in that each cell was capable of an autonomous existence and could give rise to a complete new organism. Although Schleiden and Schwann did not put their theories to the test they laid the foundations for the concept of TOTIPOTENCY.