- All organisms are made up of cells.
- The cell is the basic unit of life.
- All cells come from other cells.
The previous postulates were created thanks to studies carried out using a microscope in 1665. It was in that year that the first cells were observed .
On the other hand, it was Robert Hooke who named the “cell” as such and also gave it the description of “basic units of organisms .” His studies were based on an inert material.
Years later, the microscope was improved by Anthony van Leeuwenhoek and he observed living cells and microorganisms for the first time.
However, the criteria of cell theory are defined 200 years later. The first two postulates of the cell theory were proposed by Theodor Schwann and Matthias J. Scheiden respectively.
Importance of cell theory
The three postulates of the cell theory served to diminish a little the existing division on the possible origins of life.
Thanks to the microscope and to Anthony van Leeuwenhoek and his visualization of living cells, it was found that all living organisms have cells, these being the basic unit of life and from which “other lives” are born.
From the postulates it has been possible to study other biological elements such as molecules. These particles may have existed in the universe before the first cells were formed.
Examples of cell theory
As we said before, the biologist Theodor Schwann and the botanist Matthias J. Scheiden would generate the first two postulates. Over the years a third postulate was added and together they make up the cell theory since 1830:
The cell is the basic unit of life: Theodor Schwann proposes that the cell is a structural unit and that all organisms are composed of cells, since it is the basic structure of life.
All life is made up of cells: this postulate is the creation of the German Matthias Schleiden, who says that the cell is a functional unit of organisms: they contain all the vital or fundamental functions for life. The most important function being that of reproducing other organisms from processes that were later defined (cell division: mitosis and meiosis).
All cells come from other cells: Robert Remak, starting from the second postulate, defines that every cell has a series of information that is inherited to other cells when they are created from cell division. This discovery is important in the study of genetic inheritance.
Around this postulate there was a controversy, and that is that the credit was awarded to Rudolf Virchow, however, it was later known that it was a plagiarism of Remak’s studies.