BIOCHEMISTRY - Main Regulators and Biological Fluids of the Human Body - 2016

4. CHEMICAL COMPOSITION OF URINE

Like Blood, urine is frequently the subject of biochemical research conducted on athletes. Analysis of urine provides insight into a person's functional state and the biochemical shifts occurring in their body during physical exertion.

4.1. General Characteristics of the Kidneys

The combined mass of both human Kidneys is approximately 300 g (0.5% of body weight). At the same time, the kidneys consume 25% of the total blood volume and 10% of all oxygen entering the body. This indicates a high metabolic intensity in the kidneys, including tissue Respiration, which points to an exceptionally high energy consumption by the kidneys.

The primary function of the kidneys is Urine Formation, through which they maintain the constancy of the body's internal environment (Homeostasis). Specifically, the kidneys ensure:

- excretion of End products of Nitrogen METABOLISM;

- maintenance of acid-base balance;

- regulation of Water and Salt Metabolism;

- Maintenance of the required Osmotic Pressure of Body Fluids;

- Regulation of Blood pressure.



Last update: 06/08/2026

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