THORAX ABDOMEN AND PELVIS

Detailed explanation-1: -Intraperitoneal organs include the stomach, spleen, liver, first and fourth parts of the duodenum, jejunum, ileum, transverse, and sigmoid colon.

Detailed explanation-2: -Intraperitoneal: peritonealized organs having a mesentery, such as the stomach, small intestine (jejunum and ileum), transverse colon, liver and gallbladder. Retroperitoneal: organs without a mesentery and associated with posterior body wall, such as the aorta, inferior vena cava, kidneys and suprarenal glands.

Detailed explanation-3: -The appendix, transverse colon, and sigmoid colon are intraperitoneal organs. The cecum also is located intraperitoneally, but it lacks a mesentery. The cecum is an intraperitoneal organ, however, as it is covered on all sides by peritoneum.