Who proposed the cell theory?
The cell theory was given by Matthias Jacob Schleiden (Mathias Jacob Scliden, 1838) and Theodore Schwann (Theodore Schwann, 1839). He said that the body of plants and animals is made up of cell and cell products.
Rudolf Virchow first reported that Omnis Cellulaie Cellula means all cells arise from pre-existing cells, that is, the cell divides, and that new cells are produced by the division of pre-existing cells. It occurs from
Modern cell theory
Rudolf Virchow changed this theory of Schleiden and Schwann into a new cell theory, which is called modern cell theory. according to to-
- Each living body is made up of one or more cells.
- The cell is the structural and functional unit of living organisms.
- All cells are the same. Which contains Cytoplasm, Nucleus, and Organelles.
- The cell is covered with a thin cell membrane and cell wall. The cell wall is found only in plant cells, not in animal cells.
- The chemical organization and metabolic reactions of all cells are the same. Therefore, the cell is called a fundamental unit of living being.
- New cells are formed by the division of the preceding cells.
- Cells present genetic material that is inherited from one child to another. Therefore a cell can be called a unit of heredity.
The exception of Cell Theory
Exceptions to cell theory are:
Viruses are unicellular and contain only nucleic acids (DNA or RNA) and proteins.
- Virus (Viroids)
Viroids are called only RNA particles.
These are inactive carriers of the viral genome.
- Preeon ( Prions)
These are the outer only proteins of the virus, in which nucleic acids are absent.
- Red blood cells (RBC)
The nucleus is absent in the mammals of mammals. Camels and lamas have nuclei present in RBCs.
Formative genetic material is absent in B and T lymphocytes.
These are called exceptions for the following reasons –
- They lack cell membranes, organisms, cells, enzymes, and other cellular components.
- They do not have the capability of segmentation. They require a live host cell for division.
- Generally, only one of the DNA or RNA is present. While both nucleic acids are found in each cell.
Who proposed the cell theory? Morden Cell Theory,& Exception