Other than blood, number of body fluid also can be tested in the laboratory because they can provide more precise information about what might be happening in a specific area of the body. Typically, samples are acquired by collecting the fluid (such as urine or semen) in a container or by aspirating some of the fluid with a syringe after introducing a needle into a bodily cavity (CSF, pericardial fluid, etc.). Once a sample has been collected, various testing, such as chemical checks, microscopic analyses, and infectious disease tests, may be carried out.