Bilirubin Excretion
When a red blood cell reaches around 120 days of age, it begins to disintegrate. During this process, the hemoglobin within the red blood cell breaks down into four components: globin, protein, iron, and heme. The heme component eventually converts into a pigment known as bilirubin, which has an orange-yellow color.
After its formation, bilirubin travels to the liver, where it undergoes a series of chemical changes to become more soluble. In the liver, it combines with bile, a digestive fluid produced by the liver, and is then excreted from the body through the excretory system. The excretion of bilirubin occurs via two main routes: it is eliminated as a component of feces and also excreted in urine.
The Role of the Liver in Fat Metabolism
One of the important functions of the liver is to metabolize fats. When the body’s glycogen stores are full, any excess glucose is converted into fatty acids. These fatty acids, along with cholesterol, are transported through the bloodstream and stored in fat tissues. However, an excessive accumulation of fat in the liver can lead to a condition known as fatty liver disease, which can adversely affect its overall function.