1. Blood Purification: As a result of metabolism, nitrogenous waste products – urea, uric acid, creatinine etc. are created in the human body. These waste materials are excreted from the body through the kidneys. As a result blood is purified.
2. Acid-base balance: Kidneys regulate the levels of mineral salts and bicarbonate in the body. It regulates the acid-base balance in the blood.
3. Water balance: Kidneys regulate water balance in the body through osmoregulation.
4. Temperature regulation: It regulates temperature throughout the body.
5. Vitamin production: Kidneys produce vitamin D in the body.
6. Blood cell production: Erythropoietin hormone is produced in kidney. Erythropoietin makes red blood cells in the body.
7. Blood pressure regulation: Kidneys regulate blood pressure in the body with the help of various hormones.
8. Hormone production: Kidney produces hormones like erythropoietin, prostaglandin, angiotensin, calcitriol etc. in the animal body.
9. Removal of toxins: It removes toxins from the body.
10. Mineral salts: Kidney controls the amount of sodium, potassium, calcium, phosphate, chloride etc. in the human body.
11. Gluconeogenesis: In the process of gluconeogenesis, sugar is produced from proteins and lipids. Gluconeogenesis occurs during prolonged starvation. During this time the kidney can supply about 20% glucose.
12. Enzyme secretion: Renin enzyme is secreted from kidney. Renin acts like an enzyme hormone.
13. Regulation of Osmosis: Kidneys regulate the osmotic pressure between blood and cells-tissues in the body.
14. Bone and teeth formation: Kidney plays a major role in vitamin-D production. Vitamin-D regulates calcium levels in the blood. Calcium forms bones and teeth.
15. Homeostasis: Homeostasis is the internal orderly environment of the body. Kidneys maintain homeostasis in the body by removing waste products from the blood.