31. The gastrovascular cavity itself is divided into a number of chambers by mesenteries radiating inwards from the body wall. 32. Many of the mesenteries project into the enteric cavity but some extend from the body wall to the central stomodaeum. 33. Volvulus occurs when a portion of the bowel twists around its mesentery , which can lead to obstruction and infarction. 34. Adult flatworms parasitize blood capillaries of either the mesenteries or plexus of the bladder, depending on the infecting species. 35. The septa are secreted by the mesenteries , and are therefore added in the same order as the mesenteries are. 36. The septa are secreted by the mesenteries, and are therefore added in the same order as the mesenteries are. 37. Polyps may also grow in the stomach, duodenum, spleen, kidneys, liver, mesentery and small bowel. 38. This is criss-crossed by various mesenteries which provide support for the pharynx and the rest of the gut. 39. The next lymph sac to appear is the unpaired retroperitoneal lymph sac at the root of the mesentery of the intestine. 40. Inside the body wall is the coelom which is divided by three longitudinal mesenteries which surround and support the internal organs.
