The main role of the kidney is fluid regulation. Besides maintaining the blood volume, the kidneys control fluid loss from the body, especially the amount of extracellular fluid. The kidneys secrete renin, an enzyme that acts as a hormone, which stimulates the adrenal cortex to release aldosterone. This hormone increases the rate at which Na is reabsorbed by the nephrons. This hormone ensures that the correct proportions of sodium and potassium are maintained in the body.
The proximal tubule consists of capillaries that connect to a hollow enlargement called Bowman’s capsule. These capillaries are located in the cortex of the kidney. The proximal tubule, which remains within the outer layer of the kidney, is the main site for reabsorption of water and solutes. Eventually, this segment is surrounded by a layer of tissue called medulla.
The kidney excretes various waste products into the urine. These waste products are filtered out of the blood by the nephron, a microscopic structural unit. These wastes are nitrogenous and include urea and uric acid, which are derived from protein catabolism and nucleic acid metabolism. In mammals and birds, these waste products are concentrated into a small volume of urine by the nephron, which relies on a countercurrent multiplication mechanism.
The main purpose of the kidney is to filter out potentially harmful waste products from the blood. The kidneys filter out toxins and excess fluid, and they also regulate the body’s pH. In addition to filtering out the toxins in the blood, the kidneys also remove bicarbonate from the urine. These waste products are important for the functioning of nerves and cells. The kidney is responsible for approximately 20 percent of the heart’s output.
The kidneys are responsible for maintaining the pH balance in the blood, which is a delicate equilibrium. Blood pH should be 7.35 to 7.45, but outside of this range can result in an imbalance of acidic and basic blood. Therefore, the kidneys maintain a constant pH balance by excreting excess acids and bases. They also retain necessary amounts of water in the body. If the kidneys fail to maintain this balance, the body can become dehydrated and swollen.
Another function of the kidney is the regulation of calcium and phosphate. Both calcium and phosphate are required for bone growth, and when a person’s kidneys are impaired, this can lead to weak bones. Keeping a healthy diet and a healthy physical schedule are crucial for maintaining a healthy kidney. If you are concerned about your kidney’s health, consult a doctor immediately. If you are having difficulty with the process of regulating calcium and phosphate, you should seek medical attention immediately.
During the summer, urine volume decreases because of perspiration. Conversely, it increases in the winter months because there is less perspiration and more urine. A volume of less than 500 ml suggests a problem with the kidneys. If it is more than three liters, the kidneys are functioning abnormally. However, it is important to note that kidneys require adequate blood supply. Therefore, narrowed blood vessels can prevent the proper functioning of the kidney.