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Urine

life science Maturity 11-13 Next article →

Urine is a liquid made by the kidneys of vertebrates. It is a very important way for the body to stay healthy. The kidneys use urine to clear the bloodstream of extra water. They also remove metabolic by-products, which are waste materials from the body. These wastes include urea, uric acid, and creatinine.

Human urine sample
Human urine sample

By getting rid of these things, the body keeps its internal balance. This process is a key part of how living things stay clean on the inside.

In humans, the urinary system works in a specific way. First, the kidneys filter the blood to extract wastes and extra water. This creates urine, which contains high levels of urea and other substances. Next, the urine flows through two tubes called ureters. These tubes carry the liquid to the urinary bladder for storage.

Harnstoff
Harnstoff

When it is time, the urine leaves the bladder through the urethra. This path helps the body move waste from the inside to the outside.

People have studied urine for a very long time. In ancient history, many doctors looked at urine to understand health. A writer named Hermogenes wrote about how urine color could show diseases. Later, in the year 862 AD, Abdul Malik Ibn Habib wrote about urine in the Umayyad empire.

Bigot, Trophime - A Doctor Examining Urine
Bigot, Trophime - A Doctor Examining Urine

This practice of looking at urine is called uroscopy. Today, doctors use much more advanced tests to check urine for health.

Urine is mostly made of water, about 91 to 96 percent. The rest of the liquid contains salts, urea, and organic compounds. In a healthy person, urea is the largest part of the solid material. On average, an adult human produces about 800 to 2,000 milliliters of urine every day.

Urine under the microscope
Urine under the microscope

This amount can change based on how much water you drink or how active you are. It also depends on your weight and your general health.

Urine can tell us many things about the world and our bodies. For example, the color often changes based on how much water you drink. Dark yellow urine can mean you are dehydrated.

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

In nature, urine helps the earth's nitrogen cycle. It can act as a fertilizer to help plants grow in balanced ecosystems. Some animals even use urine to mark their territory.

Urinating dog (7768361246)
Urinating dog (7768361246)

This helps them communicate with other animals in their environment.

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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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