Final answer:
Biliverdin and bilirubin are both bile pigments derived from the breakdown of heme from red blood cells. Biliverdin is a green pigment that is converted into the yellow-brown pigment bilirubin in the liver. These pigments are initially water-insoluble but become water-soluble after the liver processes them, allowing for excretion through the bile.
Step-by-step explanation:
Biliverdin and bilirubin are both bile pigments produced from the breakdown of hemoglobin when red blood cells are destroyed. Biliverdin, which is a green pigment, is first produced from the non-iron portion of heme. This biliverdin is then rapidly converted into bilirubin, a yellow-brown pigment, within the body. The process in which these pigments are handled by the body is critical for maintaining health.
Biliverdin is produced when the non-iron portion of heme is degraded. It is then further converted to bilirubin in the liver, the conversion giving rise to a change in color from green to yellow-brown. As unconjugated bile pigments, both biliverdin and bilirubin are initially insoluble in water. The liver plays a crucial role in converting these pigments into a water-soluble form, through conjugation processes. Bilirubin binds with albumin in the blood and then is taken to the liver, where it is converted into bilirubin mono- and di-glucuronide, also termed conjugated bile pigments, which are water-soluble and can be excreted out of the body via bile into the intestine. In the large intestine, bacteria can further convert bilirubin into stercobilin, which contributes to the brown color of feces. If the liver is not functioning properly or if bile ducts are blocked, bilirubin cannot be excreted effectively and may cause jaundice, a yellowish discoloration of the skin and eyes.