An element is a pure substance that is made from a single type of atom. Elements are the building blocks for all the rest of the matter in the world. Examples of elements include iron, oxygen, hydrogen, gold, and helium.
Since the initial discovery that the adult brain contains stem cells that generate new neurons, an important question in neurobiology has been whether or not this adult neurogenesis is functionally important.
Non-embryonic (adult) stem cells. Adult stem cells have a misleading name, because they are also found in infants and children. These stem cells come from developed organs and tissues in the body. Theyâre used by the body to repair and replace damaged tissue in the same area in which they are found. For example, hematopoietic stem cells are a type of adult stem cell found in bone marrow. They make new red blood cells, white blood cells, and other types of blood cells.