Kidney Kidney The kidneys are two bean-shaped organs found in vertebrates. They are located on the left and right in the retroperitoneal space, and in adult humans are about in length. They receive blood from the paired renal arteries; blood exits into the paired renal veins. Each kidney is attached to a ureter, a tube that carries excreted urine to the bladder. The nephron is the structural and functional unit of the kidney. Each adult kidney contains around 1 million nephrons. The nephron utilizes four processes to alter the blood plasma which flows to it: filtration, reabsorption, secretion, and excretion. The
Cystic artery Cystic artery The cystic artery (also known as bachelor artery) supplies oxygenated blood to the gallbladder and cystic duct. In the classic arrangement, occurring with a frequency of approximately 70%, a singular cystic artery originates from the geniculate flexure of the right hepatic artery in the upper portion of the hepatobiliary triangle. A site of origin from a more proximal or distal portion of the right hepatic artery is also considered relatively normal. After separating from the right hepatic artery, the cystic artery travels superiorly to the cystic duct and produces 2 to 4 minor branches, known as "Calot’s arteries",