Blood pigment of annelids is

Options

A. haemoglobin
B. cyanin
C. haemanin
D. haemocyanin

Answer

**Step-by-Step Solution:**

1. **Understanding Blood Pigments**: Blood pigments are molecules that bind to oxygen and help transport it throughout the body. They play a crucial role in respiration by ensuring that tissues and organs receive adequate oxygen.

2. **Identifying the Blood Pigments**: The common blood pigments include hemoglobin, hemocyanin, hemerythrin, and chlorocruorin. Each of these pigments has different properties and colors.

3. **Evaluating the Options**:
- **Hemoglobin**: This pigment is known for giving blood a red color and is primarily found in vertebrates, including humans. It binds with oxygen but is not the correct answer for annelids.
- **Cyanine**: This is not a blood pigment found in animals; rather, it is associated with plants. Therefore, it is not applicable here.
- **Humanin**: This pigment is bluish in color and is not found in animals, making it an incorrect choice.
- **Hemocyanin**: This is a non-heme, copper-containing pigment found in some invertebrates, including annelids. It is responsible for transporting oxygen in their blood and gives it a blue color.

4. **Conclusion**: Based on the evaluation of the options, the correct blood pigment of annelids is **hemocyanin**.

**Final Answer**: The blood pigment of annelids is **hemocyanin**.

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