Following the fecundation of an egg by a sperm, the fertilized egg begins a series of cell divisions that leads to the formation of a mass of cells known as the blastula. This mass contains two types of cell masses, the trophoblast, and the inner cell mass. The trophoblast leads to the formation of the…
Adult stem cells or adult tissue-specific stem cells are non-embryonic stem cells that are found in the tissues and organs of adults. They have the specific characteristics of self-renewal and generate differentiated and specialized cells that contribute to tissue homeostasis and regeneration following injuries or diseases. They are found in several organs including the brain,…
For a long time, the brain was thought to exclusively contain finally differentiated cells, such as neurons, astrocytes, and oligodendrocytes. These highly specialized cells are originated during embryonic development and their number decreases throughout adulthood. However, from 1962, Joseph Altman and his colleagues challenged this dogma by demonstrating that the brain contained other types of…
