The Clinical Measurement Ontology (CMO), Measurement Methods Ontology (MMO), and Experimental Condition Ontology (XCO) are currently being developed at the Rat Genome Database. For more information about these vocabularies please see Shimoyama et al. Three ontologies to define phenotype measurement data. Front Genet. 2012;3:87. Epub 2012 May 28 or contact us (http://rgd.mcw.edu/contact/index.shtml).
This measurement is a calculated/estimated value of the relative mass of total fluid in an organism. The two main fluid compartments are divided by the cell membrane into the extracellular fluid (ECF) and the intracellular fluid (ICF).