Cell Theory
Cell Theory is a foundational biological principle stating that all living organisms are composed of cells, established formally in the 19th century following improvements in microscopy.
Establishing that every living thing, from the simplest bacteria to the largest whale, shares the same fundamental building block, this theory became one of biology's most foundational unifying principles.
All Living Things Are Made of Cells
Cell theory establishes that all living organisms are composed of one or more cells, representing the fundamental structural and functional unit of life.
Enabled by Microscopy Improvements
Cell theory's formal establishment followed significant improvements in microscopy technology during the 19th century, allowing scientists to observe cellular structures clearly for the first time.
Cells Arise from Other Cells
A key principle of cell theory holds that new cells arise from the division of existing cells, rather than spontaneously generating from non-living matter.
A Foundational Unifying Biological Principle
Cell theory remains one of biology's most foundational unifying principles, underlying modern understanding of genetics, disease, and all biological processes.
