Extending from the caecum to the rectum, the ascending, transverse, descending and sigmoid are four sections of which part of the large intestine?
Large intestine five sections: the cecum plus the ascending colon, the transverse colon, the descending colon, the sigmoid colon, and the rectum. Sections of the colon are: The parts of the colon are either intraperitoneal or behind it in the retroperitoneum. Retroperitoneal organs in general do not have a complete covering of peritoneum, so they are fixed in location. Intraperitoneal organs are completely surrounded by peritoneum and are therefore mobile. Of the colon, the ascending colon, descending colon and rectum are retroperitoneal, while the cecum, appendix, transverse colon and sigmoid colon are intraperitoneal. This is important as it affects which organs can
Transverse folds of rectum Transverse folds of rectum The transverse folds of rectum (or Houston's valves) are semi-lunar transverse folds of the rectal wall that protrude into the rectum, not the anal canal as that lies below the rectum. Their use seems to be to support the weight of fecal matter, and prevent its urging toward the anus, which would produce a strong urge to defecate. Although the term rectum means straight, these transverse folds overlap each other during the empty state of the intestine to such an extent that, as Houston remarked, they require considerable maneuvering to conduct an instrument along the canal,