The human colon includes the cecum, ascending colon, transverse colon, descending colon, and sigmoid colon. The descending colon is part of the colon, so it also has the anatomical landmarks of the colon, i.e., colonic pouch, intestinal fat pendant, and colonic band. The descending colon is a continuation of the lower end of the transverse colon, fixed in the splenic area of the colon, and belongs to the interstitial organ of the peritoneum, covered by peritoneum in front and on both sides, and is a relatively fixed colon, with loose connective tissue behind it connected to the posterior wall of the peritoneum, so when the intestinal wall is perforated, it may cause serious retroperitoneal infection. The intestinal wall of colon has been divided into plasma muscle layer, muscle layer, submucosal layer and mucosal layer, and this area is prone to infiltrative colon tumors. Adults are recommended to do routine colonoscopy to determine the lesions in the colon in time. If there is no abnormality in colonoscopy, it can be followed up and observed for 2-4 years. If there is no abnormality in the colonoscopy, it can be followed up for 2-4 years. Try to develop good habits of life and rest, don’t be too stressed and don’t stay up late.