Cellular differentiation
Cellular differentiation is a concept from developmental biology describing the process by which cells acquire a "type". The morphology of a cell may change dramatically during differentiation, but the genetic material remains the same, with few exceptions. A cell that is able to differentiate into many cell types is known as pluripotent. These cells are called stem cells in animals and meristematic cells in higher plants. A cell that is able to differentiate into all cell types is known as totipotent. In mammals, only the zygote and early embryonic cells are totipotent, while in plants, many differentiated cells can become totipotent with simple laboratory techniques.Differentiation can involve changes in numerous aspects of cell physiology; size, shape, polarity, metabolic activity, responsiveness to signals, and gene expression profiles can all change during differentiation.
In cytopathology the level of cellular differentiation is used as a measure of cancer progression.