Which organ is primarily responsible for excreting urea?

The kidneys are primarily responsible for excreting urea from the body. In the metabolic process, proteins are broken down into amino acids, which are then deaminated to remove the amino group. This process results in the formation of ammonia, which is toxic to the body. The liver converts ammonia into urea through the urea cycle, making it less harmful. Once formed, urea is released into the bloodstream and transported to the kidneys.

The kidneys filter the blood, allowing them to remove urea along with excess water and other waste products, which are then excreted as urine. This process is vital for maintaining the body’s nitrogen balance and overall homeostasis. Other organs, such as the lungs and the heart, play important roles in various bodily functions, but they do not have a significant role in the excretion of urea.