Q. “All the plants and animals are composed of cells and the cell is the basic unit of life”. The given statement is for which of the following theories?
Answer: Cell theory
Notes: The Cell theory, first developed in 1839 by Matthias Jakob Schleiden and Theodor Schwann, states that all organisms are composed of one or more cells, that cells are the fundamental unit of structure and function in all living organisms, and that all cells come from pre-existing cells. Cells are called the ‘Building Blocks of Life’ or the ‘Basic units of Life’.