endocrine glands and hormones

The thymus gland is located in the back of the sternum between your lungs.  It is only active until puberty.  After puberty, it shrinks and is replaced by fat.  Thymosin is the hormone of the thymus.  The purpose of thymosin is to stimulate the production of T-lymphocytes or T cellsT cells are white blood cells that go to the lymph nodes (immune system cells) and protect the body from certain threats, including viruses and infections.   Properly functioning, the thymus produces all of the T cells that the body needs prior to puberty.