part of part_of large intestine colon Last portion of the digestive system in most vertebrates; it extracts water and salt from solid wastes before they are eliminated from the body[WP] In mammals, the colon consists of four sections: the ascending colon, the transverse colon, the descending colon, and the sigmoid colon[WP]. In zebrafish, the posterior intestine has short longitudinally arranged epithelial folds which are similar to the colon of higher vertebrates[ZFIN]. hindgut large bowel posterior intestine posterior intestine - zebrafish subdivision of digestive tract