Progress in Stem Cell Frontier

Abstract

Human life starts when a sperm combines with an ovum and forms a fertilised egg. This cell and its immediate descendents, are called "totipotent stem cells". During first 8 weeks of human life, embryonic stage, the embryo is made of specialised "embryonic stem cells” also called “pluripotent stem cells” that can form just about every cell except the placenta. In the course of human development a single fertilised egg, ultimately gives rise to more than 200 cell types (blood cells, neural (brain) cells, liver cells etc) which make up the human body. This process, whereby less