The Cell Theory was proposed by M. J. Schleiden and Theodor Schwan.
Scheleiden prepared the cell theory in plants of 1838 and Schwan prepared the cell theory of animals in 1839.
The salient features of it are:
. Cell is the unit of structures.
. Cell is the unit of function.
. Cell is the unit of heredity.
. All living cells arise only from the pre-existing cells.
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