the jejunum is present in the upper left quadrant whereas the ileum is present in the bottom right quadrant as well as within the pelvis
The jejunum and ileum differ slightly in blood supply
the jejunum is more vascularised than the ileum and so it has a dark red appearance compared with the paler pink appearance of the jejunum
the Jejunum has Long thick vasa recta
the ileum has thin and smaller but many vasa recta
the Jejunum has short thick arterial arcades
the Ileum has long thick arterial arcades
there are many layers (11) to the Jejunum & Ileum
From superficial to deep it goes like this
Serosa (visceral peritoneum)
• Subserosa
• Longitudinal layer muscularis externa
• Myenteric plexus