Question

which of the following is the correct sequence in the breakdown of the non - iron portion of the heme?
multiple choice
heme, bilirubin, biliverdin, urobilinogen, feces
heme, biliverdin, bilirubin, urobilinogen, feces
heme, bilirubin, urobilinogen, biliverdin, feces
heme, biliverdin, urobilinogen, bilirubin, feces

Explanation:

When the non - iron portion of heme is broken down, heme is first converted to biliverdin by the enzyme heme oxygenase. Then, biliverdin reductase converts biliverdin to bilirubin. Bilirubin is then conjugated and excreted. In the intestines, bacteria convert conjugated bilirubin to urobilinogen. Some urobilinogen is excreted in feces.

Answer:

Heme, biliverdin, bilirubin, urobilinogen, feces