3. (Aeronautics) any structure corresponding to or resembling the keel of a ship, such as the central member along the bottom of an aircraft fuselage. 4. (Biology) biology a ridgelike part; carina. 5. a poetic word for ship.
Transverse colon and sigmoid colon. The transverse colon and the sigmoid colon have a mesentery (ie, transverse mesocolon and sigmoid mesocolon, respectively), but the ascending colon and descending colon are retroperitoneal, while the cecum is intraperitoneal but uses the mesentery of the ileum.
Sigmoid colon: The final S-shaped length of the colon, curves inward among the coils of your small intestine, then empties into the rectum. Rectum: The final section of digestive tract measures from 1 to 1.6 inches (or 2.5 to 4 cm). Leftover waste collects there, expanding the rectum, until you go to the bathroom.