ORGAN FUNCTION Organ function is assessed by measuring how

Organ function is assessed by measuring how well an organ is doing what it is supposed to be doing. For example, the pump function of the heart is studied by measuring the cardiac output and the blood pressure; the cognitive function of the brain is investigated using intelligence tests. The functional status of synthetic organs, organs of cell generation (such as the marrow), organs of elimination, and organs of absorption can also be evaluated. The laboratory studies used to make these measurements may assay the organ's function directly, such as analyzing semen to determine testicular function. More often, though, the studies assess function only indirectly, using the blood or plasma concentration of some secreted, eliminated or absorbed substance as a quantitative marker of the functional status.