Metabolism occurs primarily in which organ?

Metabolism occurs primarily in which organ?

• A. Heart
• B. Lungs
• C. Kidneys
• D. Liver

Answer: (D)

Metabolism is the set of chemical reactions that sustain life, and the liver is the central processing organ for these reactions. The liver houses hepatocytes with a wide array of metabolic enzymes that handle carbohydrate, fat, and protein metabolism, synthesize essential molecules, and detoxify drugs and toxins. It receives nutrient-rich blood from the digestive tract via the portal vein, allowing it to regulate blood glucose by storing excess glucose as glycogen or releasing glucose when needed. It also performs the urea cycle to remove ammonia, metabolizes lipids, and produces bile for digestion. While the heart powers circulation, the lungs enable gas exchange, and the kidneys handle filtration and some waste processing, none cover the broad, interconnected suite of metabolic activities performed by the liver. Therefore, metabolism occurs primarily in the liver.

Metabolism is the set of chemical reactions that sustain life, and the liver is the central processing organ for these reactions. The liver houses hepatocytes with a wide array of metabolic enzymes that handle carbohydrate, fat, and protein metabolism, synthesize essential molecules, and detoxify drugs and toxins. It receives nutrient-rich blood from the digestive tract via the portal vein, allowing it to regulate blood glucose by storing excess glucose as glycogen or releasing glucose when needed. It also performs the urea cycle to remove ammonia, metabolizes lipids, and produces bile for digestion. While the heart powers circulation, the lungs enable gas exchange, and the kidneys handle filtration and some waste processing, none cover the broad, interconnected suite of metabolic activities performed by the liver. Therefore, metabolism occurs primarily in the liver.