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 a few exceptions. A cell that is able to differentiate into
many cell types is known as "pluripotent". These are also known as stem
cells. 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.