Difference Between Liver and Kidney

Liver vs Kidney

Liver and Kidneys are both organs in the organisms. Especially vertebrates have a well-developed organ system among other animal groups. A collection of different types of tissues organized to perform a particular function or functions is known as an ‘organ’. Therefore, a tissue is the functional and structural unit of an organ. An organ system is composed of a group of organs that performs a particular function in the body. Basically, the vertebrates have 11 principal organ systems, which perform major activities in the body and keep the vertebrates alive. The primary function of kidney and liver is to expel or remove toxic substances that result from the metabolic reactions in the animal body. Even though both these organs do the same primary function, they are different in many aspects.


The liver is the largest internal organ that performs as many as 500 important functions in the human body. It is located on the right side of the abdomen and protected by the rib cage. The liver stores glucose, fats, and many other micronutrients such as iron, copper, and many vitamins. It releases these substances as the body needs them, thus the liver helps ensure a constant supply of energy rich molecules for body cells.

The liver is capable of synthesizing blood proteins involved in clotting and detoxifying toxic or harmful chemical substances like nicotine, barbiturates, and alcohol in the body. It also plays a major role in the process of digestion by producing the substance called bile, which is essential for lipid digestion. Bile is a fluid mixture, consisting of bile pigments and bile salts. It is stored and concentrated in the gallbladder.


The kidney is a complex organ made of thousands of tiny units called nephrons. Nephrons are the basic functional and structural unit of the kidney. The mammalian kidneys have two types of nephrons, namely, juxtamedullary nephron and cortical nephron. All the vertebrates have the same basic structure of the kidneys while very few modifications have occurred among certain vertebrate groups. In general, functions of the kidneys include eliminating metabolic waste products, regulating body water concentration and blood pressure, and maintaining a constant blood pH.

Humans have two bean shaped kidneys that are located in the posterior abdominal wall beneath the diaphragm, and lie on either side of the vertebral column. Each kidney is served by a renal artery, which receives blood and, from this blood, urine is produced. Urine then drains to a urinary bladder through a ureter. The three major functions of human kidneys are filtration of fluid in the blood, reabsorption of important solutes (such as glucose, amino acids, inorganic salts etc.) from filtrate, and secretion of certain substances from the extracellular fluid into the filtrate.

What is the difference between Liver and Kidney?

• Liver is an organ of the digestive system while kidneys are the organs of the urinary system.

• Each individual contains one liver and two kidneys in their body.

• Liver excretes bile pigments as a metabolic waste of hemoglobin breakdown whereas kidney excretes ammonia, urea, uric acid, urochrome, water, and certain inorganic irons such as waste products.

• Unlike kidney, the liver stores glucose and fat. Filtration and reabsorption of glucose can be done by kidneys.

• The structural and functioning unit of the kidney is nephron.