Bilirubin and biliverdin are derived from

Options

A. Globulin
B. Heme
C. Iron
D. Fat

Answer

**Step-by-Step Solution:**

1. **Understanding the Components**: Begin by recognizing that bilirubin and biliverdin are both pigments associated with the breakdown of hemoglobin. Hemoglobin is composed of two main components: heme and globin.

2. **Identifying the Source**: Focus on the heme component of hemoglobin. The heme group is crucial because it is the part that contains iron and is responsible for binding oxygen. When hemoglobin is broken down, it is the heme that is cleaved to produce biliverdin.

3. **Formation of Biliverdin**: When the heme group is broken down, it is cleaved at the alpha-methene bridge, resulting in the formation of biliverdin. Biliverdin is a green pigment and consists of four linearly connected pyrrole rings, making it a tetrapyrrole.

4. **Conversion to Bilirubin**: Biliverdin is then further reduced to bilirubin, which is a yellow pigment. This conversion is facilitated by the enzyme biliverdin reductase.

5. **Conclusion**: Therefore, both bilirubin and biliverdin are derived from the heme group of hemoglobin.

**Final Answer**: Bilirubin and biliverdin are derived from **heme**.

---