In general they are all called peritoneal serous membranes. They too are secreting slippery fluids to reduce friction. What organs in the abdominopelvic cavity would you imagine need to have this low friction fluid around their outside?

In the abdominopelvic cavity, **peritoneal serous membranes** (comprising the parietal and visceral peritoneum) envelop various organs to secrete serous fluid. This fluid acts as a lubricant, reducing friction and allowing organs to move smoothly relative to each other and the abdominal wall. The following organs are typically surrounded by these low-friction fluids due to their need for mobility and interaction within the cavity: 1. **Stomach**: The visceral peritoneum covers the stomach, facilitating its movements during digestion. 2. **Small Intestine**: - **Jejunum** - **Ileum** These sections are enveloped to allow the constant movement required for nutrient absorption. 3. **Large Intestine (Colon and Rectum)**: Covered to support peristaltic movements and positional adjustments. 4. **Liver**: The largest internal organ, surrounded by peritoneum to accommodate its extensive range of functions and movements. 5. **Spleen**: Enveloped by serous membranes to allow its role in filtering blood and immune responses without causing friction. 6. **Gallbladder**: Covered to enable its contraction and movement during bile release. 7. **Pancreas**: While primarily retroperitoneal, certain parts are covered by peritoneum, aiding in its digestive and endocrine functions. 8. **Ovaries and Fallopian Tubes (in females)**: These reproductive organs are suspended within the pelvic cavity by the broad ligament, which is a peritoneal fold, allowing for their necessary mobility. 9. **Uterus (in females)**: Covered by peritoneum (specifically the serosa) to permit its expansion and movements during pregnancy and menstruation. 10. **Kidneys and Adrenal Glands**: Although primarily retroperitoneal and not fully enveloped by peritoneum, their positioning is facilitated by peritoneal reflections that help reduce friction with surrounding structures. 11. **Bladder**: Partially covered by peritoneum, especially as it fills and changes shape. By surrounding these organs with serous membranes, the body ensures seamless movement and interaction within the complex environment of the abdominopelvic cavity, minimizing wear and tear and enhancing organ function. **Key Abdominopelvic Organs Enveloped by Peritoneal Serous Membranes:** - Stomach - Small and Large Intestines - Liver - Spleen - Gallbladder - Pancreas - Ovaries and Fallopian Tubes (in females) - Uterus (in females) - Parts of the Kidneys and Bladder These coverings provide the necessary lubrication to facilitate their movements and interactions within the abdominal and pelvic regions.