What metabolic change occurs when heme is broken down?

When heme is broken down, the metabolic change that occurs is its catabolism into biliverdin. This process is part of the broader pathway of heme degradation, which begins with the enzyme heme oxygenase that cleaves heme to produce biliverdin, carbon monoxide, and free iron. Biliverdin is then further reduced to bilirubin, which has important implications for various bodily functions and is mainly processed in the liver.

The choice of biliverdin as the correct answer reflects a fundamental aspect of heme metabolism in the body. This pathway is crucial in the context of managing waste products and maintaining the balance of various compounds, particularly in terms of bilirubin, which can have physiological effects and plays a role in the digestive process after being conjugated in the liver.

Other options do not accurately reflect the metabolic pathways associated with heme degradation. Heme is not converted into glucose or fatty acids; these processes involve entirely different metabolic pathways focused on energy production and storage rather than the breakdown of heme. Likewise, heme does not directly form cholesterol in its metabolic cascade. The emphasis on biliverdin's role thus underscores the significance of understanding how heme is processed in biological systems.