Jejunum
The jejunum lies between the duodenum and the ileum and is considered to start at the suspensory muscle of the duodenum, a location called the duodenojejunal flexure. The division between the jejunum and ileum is not anatomically distinct due to the fact that in adult humans, the small intestine is usually 6-7m long, about two-fifths of which (2.5 m) is the jejunum.
Small intestine (Chinese medicine)
Transporting point of SI: Urinary Bladder 27. Conception vessel – anterior midline from perineum to lower lip. This is also the Alarm point for the SI which is called "Gateway to the Source"(guan yuan). Governing vessel is from perineum, to spine to crown of head down to upper lip.