Euplectella

Options

A. Has skeleton of siliceou spicules which are triaxon with three rays
B. Live in commensal relationship wth shrimp and shrimps are benefited in this relationship
C. Provide shelter for male and female shrimp and till death both male and female shrimp live together. So it is a precious marriage gift in japan
D. Both (2) & (3)

Answer

**Step-by-Step Solution:**

1. **Identify the Classification of Euplectella**:
- Euplectella is classified under the phylum Porifera and belongs to the class Hexactinellida.

2. **Understand the Skeleton Structure**:
- The skeleton of Euplectella is made up of siliceous spicules, specifically triaxon spicules. These spicules are characterized by having six rays.

3. **Examine the Relationship with Shrimp**:
- Euplectella is known to live in a commensal relationship with shrimp. In this relationship, the shrimp benefit from the shelter provided by Euplectella.

4. **Discuss the Significance in Culture**:
- In Japan, Euplectella is considered a precious marriage gift. It symbolizes the bond between male and female shrimp, which live together in the sponge until death.

5. **Evaluate the Options**:
- Option 1 states that the skeleton has three rays, which is incorrect since it has six rays.
- Option 2 correctly states that it lives in a commensal relationship with shrimp, benefiting the shrimp.
- Option 3 correctly mentions that it provides shelter for male and female shrimp and is used as a marriage gift in Japan.

6. **Conclusion**:
- Since options 2 and 3 are correct, the final answer is that both options 2 and 3 are correct, leading to the conclusion that option 4 is the correct choice.