The cell theory is composed of 3 postulates and depending on the author, sometimes 4 postulates.
1- The cell is the structural unit: it states that all living beings are composed of cells.
2- The cell is the functional unit: It states that all the processes necessary for life occur in the cell.
3- The cell is the unit of origin: It states that every cell comes from another pre-existing cell.
4- The cell is the genetic unit: It states that all hereditary information is found inside the cell.
