Organs of the abdominal cavity include the stomach, liver, gallbladder, spleen, pancreas, small intestine, kidneys, large intestine, and adrenal glands.
The abdominal cavity is lined with a protective membrane termed the peritoneum. The inside wall is covered by the parietal peritoneum. The kidneys are located in the abdominal cavity behind the peritoneum, in the retroperitoneum. The viscera are also covered by visceral peritoneum.
Between the visceral and parietal peritoneum is the peritoneal cavity, which is a potential space. It contains serous fluid that allows motion. This motion is apparent of the gastrointestinal tract. The peritoneum, by virtue of its connection to the two (parietal and visceral) portions, gives support to the abdominal organs.
The peritoneum divides the cavity into numerous compartments. One of these the lesser sac is located behind the stomach and joins into the greater sac via the foramen of Winslow. Some of the organs are attached to the walls of the abdomen via folds of peritoneum and ligaments, such as the liver and others use broad areas of the peritoneum, such as the pancreas. The peritoneal ligaments are actually dense folds of the peritoneum that are used to connect viscera to viscera or viscera to the walls of the abdomen. They are named in such a way as to show what they connect typically. For example, the gastrocolic ligament connects the stomach and colon and the splenocolic ligament connects the spleen and the colon, or sometimes by their shape as the round ligament or triangular ligament.
Mesenteries are folds of peritoneum that are attached to the walls of the abdomen and enclose viscera completely. They are supplied with plentiful amounts of blood. The three most important mesenteries are mesentery for the small intestine, the transverse mesocolon, which attaches the back portion of the colon to the abdominal wall, and the sigmoid mesocolon which enfolds the sigmoid colon.
The omentum are specialized folds of peritoneum that enclose nerves, blood vessels, lymph channels, fatty tissue, and connective tissue. There are two omenta. First, is the greater omentum that hangs off of the transverse colon and greater curvature of the stomach. The other is the lesser omentum that extends between the stomach and the liver.