page_title: Urine
section_title: Constituents
hierarchical_section_title: Urine / Characteristics / Constituents
caption_attribution_description: English: This photo was taken with an Iphone X and it represents a urine slide under the microscope; in the middle of the picture there are some uric acid crystals.
context_page_description: Urine is a liquid by-product of metabolism in humans and in many other animals. Urine flows from the kidneys through the ureters to the urinary bladder. Urination results in urine being excreted from the body through the urethra.
  Cellular metabolism generates many by-products that are rich in nitrogen and must be cleared from the bloodstream, such as urea, uric acid, and creatinine. These by-products are expelled from the body during urination, which is the primary method for excreting water-soluble chemicals from the body. A urinalysis can detect nitrogenous wastes of the mammalian body.
  Urine has a role in the earth's nitrogen cycle. In balanced ecosystems, urine fertilizes the soil and thus helps plants to grow. Therefore, urine can be used as a fertilizer. Some animals use it to mark their territories. Historically, aged or fermented urine was also used for gunpowder production, household cleaning, tanning of leather and dyeing of textiles.
  Human urine and feces are collectively referred to as human waste or human excreta, and are managed via sanitation systems. Livestock urine and feces also require proper management if the livestock population density is high.
context_section_description: About 91-96% of urine consists of water. Urine also contains an assortment of inorganic salts and organic compounds, including proteins, hormones, and a wide range of metabolites, varying by what is introduced into the body.
  The total solids in urine are on average 59 g per person per day. Organic matter makes up between 65% and 85% of urine dry solids, with volatile solids comprising 75–85% of total solids. Urea is the largest constituent of the solids, constituting more than 50% of the total. On an elemental level, human urine contains 6.87 g/L carbon, 8.12 g/L nitrogen, 8.25 g/L oxygen, and 1.51 g/L hydrogen. The exact proportions vary with individuals and with factors such as diet and health. In healthy persons, urine contains very little protein and an excess is suggestive of illness.
caption: Urine under the microscope
exif: {"Image Make": "Apple", "Image Model": "iPhone 6s", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "VSCO", "Image DateTime": "2019:06:20 12:38:35", "Image Copyright": "Copyright 2019. All rights reserved.", "Image ExifOffset": "218", "EXIF ExposureTime": "1/100", "EXIF FNumber": "11/5", "EXIF ExposureProgram": "Program Normal", "EXIF ISOSpeedRatings": "32", "EXIF ExifVersion": "0221", "EXIF DateTimeOriginal": "2019:06:20 12:38:35", "EXIF DateTimeDigitized": "2019:06:20 12:38:35", "EXIF ComponentsConfiguration": "YCbCr", "EXIF ShutterSpeedValue": "70432/10599", "EXIF ApertureValue": "169463/74489", "EXIF BrightnessValue": "59787/9076", "EXIF ExposureBiasValue": "0", "EXIF MeteringMode": "Pattern", "EXIF Flash": "Flash did not fire, auto mode", "EXIF FocalLength": "83/20", "EXIF SubjectArea": "[2015, 1511, 2217, 1330]", "EXIF SubSecTimeOriginal": "453", "EXIF SubSecTimeDigitized": "453", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "2433", "EXIF ExifImageLength": "2608", "EXIF SensingMethod": "One-chip color area", "EXIF SceneType": "Directly Photographed", "EXIF ExposureMode": "Auto Exposure", "EXIF WhiteBalance": "Auto", "EXIF FocalLengthIn35mmFilm": "29", "EXIF SceneCaptureType": "Standard", "EXIF LensSpecification": "[2175733/524273, 2175733/524273, 11/5, 11/5]", "EXIF LensMake": "Apple", "EXIF LensModel": "iPhone 6s back camera 4.15mm f/2.2"}