There are 14 main body meridians, of which 12 meridians are named for the primary organ system they are associated with. It is important to note that in TCM, the term organs have much broader definitions and thus are not anatomically identical to the physical organs in Western Medicine. Each of the 12 meridians correspond to the 5 Yin organs, the 6 Yang organs, as well as the Pericardium and the Triple Burner. The 12 meridians run symmetrically on each side of the body, reaching the head, face, trunk and limbs. The other 2 are single meridians known as the Du or governor, and the Ren or conception. The Du and Ren meridians do not correspond to a particular organ system and run along the body's midline - Du runs along the middle of the back while Ren starts from the chin and extends to the base of the trunk.