In which of the following animal dimorphic nucleus is found

Options

A. Amoeba proteus
B. Trypanosoma gambiens
C. Plasmodium vivax
D. paramecium caudatum

Answer

To determine which animal has a dimorphic nucleus, we will analyze the characteristics of the nuclei in the given options.

### Step-by-Step Solution:

1. **Understand Dimorphic Nucleus**:
- A dimorphic nucleus refers to the presence of two different types of nuclei within a single organism. This means that the organism has two distinct nuclear forms, which serve different functions.

2. **Evaluate the Options**:
- **Amoeba proteus**: This organism has a single type of nucleus, which means it does not exhibit nuclear dimorphism.
- **Trypanosoma gambiense**: Similar to Amoeba, it also has a single type of nucleus and does not show dimorphism.
- **Plasmodium vivax**: This organism does not have two different types of nuclei; it also contains a single type of nucleus.
- **Paramecium caudatum**: This organism is known to have two types of nuclei: a large macronucleus and a small micronucleus. The macronucleus is polyploid and serves vegetative functions, while the micronucleus is diploid and involved in reproduction.

3. **Conclusion**:
- Based on the analysis, the only organism that exhibits a dimorphic nucleus is **Paramecium caudatum**. Therefore, the correct answer is option 4.

### Final Answer:
**Paramecium caudatum** is the organism that has a dimorphic nucleus.