The kidneys are two bean-shaped and fist-sized organs, located in the abdomen toward the back. It normally keeps one on each side of the spine. They filter waste products of body metabolism and excrete those products in the form of urine ultimately. Depending on that process, they also bear the ability to monitor the amount of body fluid, the acid-base balance of the body, and the concentrations of electrolytes such as potassium and sodium. Each kidney consists of around a million nephrons - the tiny structural and functional units within it. A nephron is composed of a filtering unit of tiny blood vessels called a glomerulus attached to a tubule. When blood enters the nephrons, the fluid and waste products are filtered and large molecules like mostly proteins as well as some needed minerals keep back to the bloodstream. It may appear kinds of disorders when the accurate regulation of kidney is broken up. Diagnosis of kidney diseases in clinical can be detected by blood or urine tests. Some target molecules expressed on kidney tissue are also used in research.