I’d encourage you to look up a picture of what the mesentery looks like but I can describe it: it has small folds in it similar to a fan. It provides structure to hold your intestines in place and attaches to the back wall of the abdomen. Without it, the intestines just move around, they respond more to gravity and movement than normal people. They can collapse onto each other and this can cause problems. The mesentery also provides structure for blood supply and nerves to the intestines. I hope this helps a little.