Left kidney
The
kidneys
are a pair of bean-shaped organs, whose main function is the production of urine (filtration, reabsorption and concentration). The secretion and reabsorption of the kidneys is a crucial part of important systemic functions like regulation of the water and electrolyte balance, regulation of the acid-base balance. The kidney is also an endocrine organ that is part of systemic blood pressure regulation and erythropoesis due to its synthesis and secretion of renin and erythropoetin.