STEM CELLS AND CELLULAR DIFFERENTIATION 3.2 Cellular differentiation is the process that produces specialized cells. Differentiation is directed by the genetic information encoded inside the cell’s DNA. It is passed from parent to offspring As shown in the diagram above, a animal cell can differentiate itself into many cell types. This type of cell is called a stem cell. Stem cells generally occur in clumps that differentiate into different tissue layers. There are two types of stem cells. Embryonic stem cells can differentiate into any kind of cell. Tissue stem cells exist within specialized tissue and are only able to differentiate into certain types of cells. cellular differentiation stem cell

STEM CELLS AND CELLULAR DIFFERENTIATION 3.2 The blood found in an umbilical cord immediately after the birth of a child is a rich source of stem cells. These stem cells can develop into various kinds of blood cells. The blood collected from the cord can be banked (or stored) in the event it is needed later in the child’s or a sibling’s life. For diseases such as leukemia, stem cells collected from healthy blood can be injected into a patient’s blood after the diseased cells have been killed. The healthy cells then grow in the patient’s bone marrow and produce healthy, cancer-free blood cells. In complex animals, certain tissues have the ability to regenerate or repair themselves after they have been damaged. Examples include muscle, skin, and bone tissues. Other tissues, such as nerve cells, cannot regenerate naturally.