1. All living things are made up of cells. This is the fundamental principle of cell theory. Whether a single-celled organism like bacteria or a complex multi-celled organism like a human, all life forms are composed of cells.
2. Cells are the basic unit of life. Cells are the smallest unit that can carry out all the processes necessary for life, such as metabolism, growth, and reproduction. This means that cells are the building blocks of all living organisms.
3. New cells arise from pre-existing cells. This principle explains how life continues. Cells don't spontaneously appear; they always originate from the division of other, pre-existing cells.
4. Cells perform specialized functions. In multicellular organisms, cells are not just identical building blocks. They differentiate into various types, each performing specialized functions. This division of labor allows for the creation of complex tissues and organs that work together to maintain the organism.
