Urine Specific Gravity
Each day an adult excretes between 800ml and 2000mL of urine. This amount varies depending on various conditions that can influence fluid loss and fluid intake. For example, the loss of fluid through heavy sweating in hot weather reduces urine amounts. The minimum volume of urine needed to remove body wastes from an adult is about 500mL/day. The specific gravity of urine can be an indicator of disease or disruption in normal metabolism. As you recall from our earlier discussions, specific gravity measures the concentration of dissolved solids in a liquid without indicating what those solids are in the past, hydrometers were used to measure the specific gravity of urine. Today urine specific gravity can be quickly determined using a specially coated dipstick or a small refractometer. Normal urine has a specific gravity of about 1.010, with a range of 1.005 to 1.035. (Remember that pure water has a specific gravity of 1.000.) The greater the concentration of dissolved solids in the urine, the higher the specific gravity. Also, the lower the volume of excreted urine, the greater the concentration of dissolved solids—and, therefore, the higher the specific gravity. If a person’s urine has a specific gravity reading below the normal range, it may indicate that the flow of water from the body into the urine is occurring at an abnormally Normal Components of Urine
The major cations in the urine are sodium (Na+) and potassium (K+). The amount of sodium chloride excreted in the urine is about 10 to 15g each day. As you might expect, the exact amount of these ions in the urine varies with the amount in the diet. The ammonium ion (NH4+) is produced by the deamination of amino acids in the kidney. Ammonia is an important compound in the regulation of pH because it accepts a proton to form the ammonium ion, which can then be excreted in the urine. This process gives our bodies a way to remove protons from the blood. High levels of the ammonium ion...
Please join StudyMode to read the full document