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Urine

life science Maturity 11-13 Next article →

{

"text": "Urine is a liquid excreted by the kidneys of vertebrates to maintain internal balance. It serves as a primary way for the body to clear the bloodstream of excess water. It also removes metabolic by-products, which are waste materials produced by cellular processes. These wastes include urea, uric acid, and creatinine.

Human urine sample
Human urine sample

By removing these substances, the urinary system prevents toxins from building up in the body. This process is essential for the survival of almost all complex living things.\n\nIn humans and other placental mammals, the urinary system follows a specific mechanical path. The process begins in the kidneys through filtration, reabsorption, and tubular secretion. The kidneys extract soluble wastes, excess water, sugars, and other compounds from the blood. This resulting liquid flows from the kidneys through two tubes called the ureters. The ureters carry the urine to the urinary bladder, which acts as a storage vessel.

Harnstoff
Harnstoff

Finally, the urine exits the body through the urethra. \n\nUrine is composed mostly of water, which makes up about 91% to 96% of its volume. The remaining portion consists of inorganic salts, urea, organic compounds, and organic ammonium salts. Urea is the largest solid constituent, making up more than 50% of the total solids.

Urine under the microscope
Urine under the microscope

An average adult produces between 800 and 2,000 milliliters of urine per day. This volume is typically released during six to eight urinations daily. However, the exact amount depends on hydration, activity levels, and individual health. \n\nMedical professionals monitor urine to detect various health conditions. For instance, polyuria is a condition where a person produces more than 2.5 liters of urine per day. Conversely, oliguria is the production of less than 400 milliliters, and anuria is less than 100 milliliters. The pH of urine, which measures acidity, usually ranges from 5.5 to 7, with an average of 6.2.

P. 28 a chart showing urine colours and their meaning
P. 28 a chart showing urine colours and their meaning

Changes in pH can be influenced by diet, such as high protein intake or eating fruits and vegetables.\n\nThe appearance of urine, specifically its color, provides many diagnostic clues. Normally, urine is a transparent solution that ranges from colorless to amber. A pale yellow color is common due to a pigment called urobilin. Urobilin is a waste product from the breakdown of hemoglobin in aging blood cells. [IMAGE:File:Fresh Urine (Day 0; 24 March 3456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789012345

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🖼️ Images & Media (11)
File:Human urine sample.jpg
Human urine sample.jpg
File:Harnstoff.svg
Harnstoff.svg
File:Urine under the microscope.jpg
Urine under the microscope.jpg
File:P. 28 a chart showing urine colours and their meaning.jpg
P. 28 a chart showing urine colours and...
File:Urinating dog (7768361246).jpg
Urinating dog (7768361246).jpg
File:Bigot, Trophime - A Doctor Examining Urine.jpg
Bigot, Trophime - A Doctor Examining Urine.jpg
File:Urine collection in Ede, Netherlands (2920690579).jpg
Urine collection in Ede, Netherlands...
File:Urine after 4 months (28 June) (2957323941).jpg
Urine after 4 months (28 June) (2957323941).jpg
File:Fresh Urine (Day 0; 24 March) (2957323823).jpg
Fresh Urine (Day 0; 24 March) (2957323823).jpg
File:Jesus-College-MS-111 00470 235v (cropped) Ansoddau'r Trwnc.jpg
Jesus-College-MS-111 00470 235v (cropped)...
File:De urinarum differencia negocium between 1210 and 1230 ..JPG
De urinarum differencia negocium between...
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