Stem cells come from embryos that are three to five days old. During this stage, an embryo is known as a blastocyst and consists of approximately 150 cells. These type of cells are referred to as embryonic stem cells. Adult stem cells are found in small counts in most adults' bone marrow and fat.Continue Reading
Stem cells are the body’s raw materials. They are the cells from which all other cells with specialized functions originate. Under the appropriate environmental conditions in the body or laboratory, stem cells divide, forming more cells called daughter cells. These daughter cells generate into new stem cells through self-renewal. They may also differentiate into specialized cells with a very specific function, such as brain cells, blood cells, heart muscle or bone.
Sources of stem cells include bone marrow, placenta and cord tissue, amniotic fluid, teeth and umbilical cord blood. Stem cells differ depending on their source and malleability. Adult stem cells can be found in specific tissues in the body. Examples of these cells include neural stem cells, blood stem cells and skin stem cells. Stem cells can be derived by reprogramming certain cells. A clone technique called somatic cell nuclear transfer is used to create embryos as a source of stem cells.Learn more about Cells