Thymus

The Thymus is an organ responsible for the maturation of immature T-cells

Structure

 * It has an asymmetric and bi-lobed structure
 * It is approximately 5cm long and 4cm wide
 * It has a cortex and a medulla - the cortex is made of a mesh-work of epithelial reticular cells and thymocytes, the immature versions of T-cells; the medulla is made of thymocytes that are in their latter stages of development

Position

 * It is located at the anterior part of the mediastinum
 * It is posterior to the manubrium of sternum
 * Its lower portion lies over the pericardial sac
 * It is at the T4-5 level

Function

 * It is involved in the early development of the immune system and causing thymocytes to develop into T-cells
 * The size of the thymus is large in children and naturally atrophies after puberty