Which of the following is the function of kidney?

The correct answer is extract waste from blood.

Key Points

• The primary function of the kidneys is to filter and remove waste products and excess substances from the blood, which are then excreted as urine.
• Kidneys play a crucial role in maintaining the body's electrolyte balance by regulating the levels of various ions, such as sodium, potassium, and calcium.
• They are essential in maintaining the body's fluid balance by adjusting the volume of urine produced depending on the body's hydration status.
• Kidneys help regulate blood pressure through the renin-angiotensin-aldosterone system, which controls the constriction of blood vessels and fluid balance.
• They are also involved in the production of hormones like erythropoietin, which stimulates the production of red blood cells in the bone marrow.

Additional Information

• Nephron: The functional unit of the kidney. Each kidney contains about a million nephrons that filter blood and produce urine.
• Glomerulus: A network of capillaries located at the beginning of a nephron that performs the first step of filtering blood.
• Urea: A waste product formed in the liver from the breakdown of proteins, which is then filtered out of the blood by the kidneys and excreted in urine.
• Renal Cortex and Medulla: The outer and inner regions of the kidney, respectively. The cortex contains most of the nephrons, while the medulla contains the structures responsible for concentrating urine.
• Dialysis: A medical procedure used to replicate the kidney's waste removal function in individuals with kidney failure. It involves the removal of waste products and excess fluid from the blood using a machine.