Experiments to demonstrate importance of nucleus in controlling growth and heredity were performed on

Options

A. Acetabularia
B. Neurospora
C. Leucocytes
D. Starfish egg

Answer

To answer the question regarding the experiments that demonstrate the importance of the nucleus in controlling growth and heredity, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which organism was used in experiments to show the nucleus's role in growth and heredity.

2. **Identifying Key Concepts**: The nucleus is known to be the control center of the cell, responsible for regulating various cellular activities, including growth and heredity.

3. **Recalling Relevant Experiments**: One significant experiment related to the nucleus is the Hammerling nucleocytoplasmic experiment. This experiment specifically focused on the role of the nucleus in controlling cellular functions.

4. **Identifying the Organism Used**: The Hammerling experiment was conducted using the organism **Acetabularia**, a type of green algae. Acetabularia is a unicellular organism that is large and complex, making it suitable for such experiments.

5. **Eliminating Other Options**:
- **Neurospora**: This is a type of fungus and while it has been used in genetic studies, it is not the organism associated with the nucleus experiments.
- **Leucocyte**: These are white blood cells and are not typically used for experiments focused on the nucleus's role in growth and heredity.
- **Starfish**: While starfish have interesting regenerative properties, they are not the primary organism used in the context of the nucleus's role in growth and heredity.

6. **Conclusion**: Based on the above reasoning, the correct answer to the question is **Acetabularia**.

### Final Answer:
The experiments to demonstrate the importance of the nucleus in controlling growth and heredity were performed on **Acetabularia**.

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