nýrnarnar

Nýrnarnar, often referred to as the kidneys in English, are a pair of vital bean-shaped organs located in the abdominal cavity, situated on either side of the spine, just below the ribs. Their primary function is to filter waste products and excess fluid from the blood, which are then excreted from the body as urine. This filtration process is crucial for maintaining the body's electrolyte and fluid balance, as well as regulating blood pressure and producing essential hormones.

The kidneys are composed of millions of tiny filtering units called nephrons. Each nephron consists of a glomerulus, a small cluster of blood capillaries, and a tubule. Blood enters the glomerulus under pressure, where water, salts, and waste products are filtered out. The tubules then reabsorb necessary substances back into the bloodstream, while the remaining waste is concentrated into urine.

Beyond filtration, nýrnarnar play a significant role in producing erythropoietin, a hormone that stimulates red blood cell production in the bone marrow. They also help in the activation of vitamin D, which is essential for calcium absorption and bone health, and they contribute to maintaining the body's acid-base balance. Dysfunction of the nýrnarnar can lead to a range of health problems, including kidney disease and failure, impacting multiple bodily systems.