A nuclear stain haematoxylin is extracted form the ­­­­­­_________ of Haematoxylum

Options

A. Sapwood
B. Bark
C. Periderm
D. Heart wood

Answer

To answer the question "A nuclear stain haematoxylin is extracted from the ­­­­­­_________ of Haematoxylum," we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Stain**: The question mentions "haematoxylin," which is a nuclear stain commonly used in histology.

2. **Know the Source**: Haematoxylin is derived from the plant genus Haematoxylum. Specifically, it is important to know which part of the plant is used for extraction.

3. **Understand the Plant**: The full scientific name is Haematoxylum campechianum, commonly known as the logwood tree. This tree is known for its use in dyeing and as a source of haematoxylin.

4. **Determine the Part of the Plant**: The options provided are sapwood, bark, periderm, and hardwood. Among these, haematoxylin is extracted from the hardwood of the Haematoxylum tree.

5. **Conclude the Answer**: Therefore, the correct answer to fill in the blank is "hardwood."

### Final Answer:
A nuclear stain haematoxylin is extracted from the **hardwood** of Haematoxylum.

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