Blood glands of Pheretima occur in segments

Options

A. 1, 2 and 3
B. 3, 4 and 5
C. 4, 5 and 6
D. 10, 11 and 12

Answer

### Step-by-Step Solution:

1. **Understanding the Organism**: Pheretima, commonly known as earthworms, have a closed circulatory system. This means that their blood is contained within vessels and does not flow freely in the body cavity.

2. **Components of the Circulatory System**: The closed circulatory system of Pheretima includes blood vessels, a heart, capillaries, and blood glands. Each of these components plays a crucial role in the circulation of blood and the overall functioning of the organism.

3. **Function of Blood Glands**: The blood glands in Pheretima are responsible for producing blood cells and hemoglobin. Hemoglobin is a protein that carries oxygen in the blood, and in Pheretima, it is found in a dissolved form within the plasma.

4. **Characteristics of Blood Cells**: The blood cells produced by these glands are phagocytic, meaning they can engulf and digest foreign particles or pathogens, which is essential for the immune response of the organism.

5. **Location of Blood Glands**: The blood glands of Pheretima are specifically located in segments 4, 5, and 6 of the earthworm's body. This anatomical detail is crucial for identifying the correct answer.

6. **Final Answer**: Based on the information gathered, the blood glands of Pheretima occur in segments 4, 5, and 6.