GENERAL HISTOLOGY

Detailed explanation-1: -The kidney regulates plasma osmolarity by modulating the amount of water, solutes, and electrolytes in the blood. It ensures long term acid-base balance and also produces erythropoietin which stimulates the production of red blood cell.

Detailed explanation-2: -Kidneys filter the blood and remove toxins. They also regulate the salt and water balance in the blood by selectively reabsorbing salt or water depending on the body’s needs.

Detailed explanation-3: -The nephron Each kidney contains over one million microscopic filtering units called nephrons . Each nephron is made of a kidney tubule and is responsible for ‘cleaning’ the blood by removing urea, excess water and mineral ions. The nephrons reabsorb as much water as is needed by the body to maintain the water balance.

Detailed explanation-4: -Direct control of water excretion in the kidneys is exercised by vasopressin, or anti-diuretic hormone (ADH), a peptide hormone secreted by the hypothalamus. ADH causes the insertion of water channels into the membranes of cells lining the collecting ducts, allowing water reabsorption to occur.

Detailed explanation-5: -Their main job is to cleanse the blood of toxins and transform the waste into urine. Each kidney weighs about 160 grams and gets rid of between one and one-and-a-half litres of urine per day. The two kidneys together filter 200 litres of fluid every 24 hours.