stem cells

Stem cells are undifferentiated cells that have the ability to divide (proliferation) and convert to a different cell type (diferentiation). This ability allows the body to create new cells and repair the damaged parts of the body, which consists of such cells, which can not be divided.

Stem cells can be either:

• totipotent - they can be transformed into any other type of cells, including totipotent cells without restrictions; 
• pluripotent - they are descendants of totipotent cells and can produce any other cells except for totipotent cells; 
• multipotent - cells can produce only related to a given cell type (eg blood cells, ...);
• unipotent - can produce only one type of cell, but have the ability to fully recover themselves.

In the division of stem cells (proliferation) are applied three ways:

• symmetric - creating two identical cells;
• asymmetric - one retains the original phenotype, the second is already different;
• differentional - both newly formed cells have a new phenotype.