An official definition of indigenous has not been adopted by the UN system due to the diversity of the worldâs indigenous peoples. Instead, a modern and inclusive understanding of indigenous has been developed and includes peoples who:
Thymus. The thymus gland is the main organ of the lymphatic system. Located in the upper chest region, the primary function of this gland is to promote the development of specific cells of the immune system called T lymphocytes.nce mature, these cells leave the thymus and are transported via blood vessels to the lymph nodes and spleen. T lymphocytes are responsible for cell mediated immunity, which is an immune response that involves the activation of certain immune cells to fight infection.
1 They secrete parathyroid hormone which regulates calcium levels in the blood. 2  Thymus. 3  Although it is considered an endocrine gland, the thymus gland is the main organ of the lymphatic system. 4  Its primary function is to promote the development of specific white blood cells called T-lymphocytes. Thyroid and Parathyroid Glands. 2  The thyroid is a dual lobed gland located in the neck region. 3  It secretes hormones that control metabolism, growth, heart rate, body temperature, and regulate calcium levels. 4  Hormones secreted by the thyroid include thyroxin, triiodothyronine, and calcitonin.