Material of the nucleus is stained by only acidic dye

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question states that the material of the nucleus is stained by only acidic dye. This implies that the nucleus contains components that have an affinity for acidic dyes.

2. **Identifying the Components of the Nucleus**: The nucleus primarily contains nucleic acids (DNA and RNA) and proteins. DNA is negatively charged due to its phosphate backbone, which means it can interact with positively charged dyes.

3. **Acidic Dyes**: Acidic dyes are negatively charged and typically stain basic (positively charged) components. However, in the context of the nucleus, we need to consider the types of dyes that can interact with nucleic acids.

4. **Basic Dyes Staining Nucleus**: While the question states that only acidic dyes stain the nucleus, it is important to note that basic dyes (which are positively charged) are commonly used to stain nucleic acids because they bind to the negatively charged DNA and RNA.

5. **Conclusion**: The statement in the question is misleading. The nucleus is primarily stained by basic dyes due to the presence of negatively charged nucleic acids. Acidic dyes do not typically stain the nucleus effectively.

**Final Answer**: The material of the nucleus is primarily stained by basic dyes, not only acidic dyes.

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