By the start of the XX century, histologists determined that tissues created for a particular purpose all share a common source - stem cells. What makes these cells unique is that they are not specialized at all and can be used to create all kinds of composite elements that make up various tissues. For example, all blood cells are very different in structure and functionality, yet they come from the same stem cells - hemocytoblasts. Every year, scientists discover new applications for stem cells in biology and medicine. Humanity is moving towards a common goal - growing organs from scratch that work perfectly as transplants - and this goal is closer thanks to research in this area.