State the postulates of Cell theory?
Answers
Cell theory states that living things are composed of one or more cells, that the cell is the basic unit of life, and that cells arise from existing cells.
Learning Objectives
Identify the components of cell theory
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.
A component of the cell theory is that the cell is the basic unit of life.
A component of the cell theory is that all new cells arise from existing cells.
Key Terms
cell theory: The scientific theory that all living organisms are made of cells as the smallest functional unit.
Cell Theory
The microscopes we use today are far more complex than those used in the 1600s by Antony van Leeuwenhoek, a Dutch shopkeeper who had great skill in crafting lenses. Despite the limitations of his now-ancient lenses, van Leeuwenhoek observed the movements of protista (a type of single-celled organism) and sperm, which he collectively termed “animalcules. ”
In a 1665 publication called Micrographia, experimental scientist Robert Hooke coined the term “cell” for the box-like structures he observed when viewing cork tissue through a lens. In the 1670s, van Leeuwenhoek discovered bacteria and protozoa. Later advances in lenses, microscope construction, and staining techniques enabled other scientists to see some components inside cells.