Cell differentiation

• At first the cells in an embryo can grow and divide to form any type of cell. They are stem cells.
• As an embryo develops most of the cells differentiate and become specialised. Specialised cells carry out a particular function. Differentiation is essential to produce a variety of cells with different functions in multicellular organisms (animals and plants).
• Cells that have become specialised cannot later change into different kinds of cells. However, there are some stem cells in most adult tissues that are ready to start dividing to replace old cells or to repair damage in the tissues where they are found