GENERAL HISTOLOGY

Detailed explanation-1: -In biology, cell theory is a scientific theory first formulated in the mid-nineteenth century, that living organisms are made up of cells, that they are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells.

Detailed explanation-2: -Key Points. The cell theory describes the basic properties of all cells. The three scientists that contributed to the development of cell theory are Matthias Schleiden, Theodor Schwann, and Rudolf Virchow. A component of the cell theory is that all living things are composed of one or more cells.

Detailed explanation-3: -The Cell Theory Is a Unifying Principle of Biology The cell theory states that all biological organisms are composed of cells; cells are the unit of life and all life come from preexisting life. The cell theory is so established today that it forms one of the unifying principles of biology.

Detailed explanation-4: -The idea of spontaneous generation was replaced by cell theory, which states that all cells come from existing cells, not from non-living things. This process is also called biogenesis.

Detailed explanation-5: -Viruses lack the typical structure of a cell and donot perform any functions of a cell hence cell theory is not applicable to viruses.