calculated gastrointestinal tract weight gastrointestinal tract weight to body weight ratio 2019-02-14T14:07:14Z A calculated value in which the weight of the gastrointestinal tract is divided by the total weight of the body, and the result presented as a ratio, fraction, quotient or percentage, thus normalizing it to body weight and, by extension, to the size of the organism. The gastrointestinal tract is an organ system within humans and other animals which takes in food, digests it to extract and absorb energy and nutrients, and expels the remaining waste as feces. The mouth, esophagus, stomach and intestines are part of the gastrointestinal tract. CMO:0003029 VT:0010954 clinical_measurement_ontology sjwang