<unk> s are laboratory tests done on<unk>  to gain an appreciation of disease states and the function of organs. Since<unk>  flows throughout the body, acting as a medium for providing oxygen and other nutrients, and drawing waste products back to the excretory systems for disposal, the state of the<unk> stream affects, or is affected by, many medical conditions. For these reasons,<unk> s are the most commonly performed medical tests.<unk>  is obtained from one of the patient's veins by venipuncture or fingerprick, except for tests such as Arterial<unk>  gas.<unk>  is useful as it is a relatively non-invasive way to obtain cells, and extracellular fluid (plasma), from the body to check on its health. Although the term<unk>  is used, most routine tests (except for most haematology) are done on plasma or serum.
The list below includes both specific tests, and general techniques.
Blood test
Peripheral vascular examination
Drug test
Medical laboratory
TestDrugLabel
Neurological examination
Mental status examination
Clinical chemistry