ABSTRACT
As explained in Chapter 13, Section 13.2, the maintenance of tissue size and therefore of tissue function in the normal renewal tissues of the body depends upon the existence of a small number of primitive ‘stem cells’ – cells that have the capacity to maintain their numbers while at the same time producing cells that can differentiate and proliferate to replace the rest of the functional cell population. Stem cells are at the base of the hierarchy of cells that make up the epithelial and haemopoietic tissues.
