Nucleus was discovered by Robert Brown in

Options

A. Orchid root cells
B. Bean root cells
C. Maize stem cells
D. Wheat stem cells

Answer

To answer the question regarding the discovery of the nucleus by Robert Brown, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Scientist and Year**: Recognize that Robert Brown is the scientist who discovered the nucleus, and this discovery took place in the year 1831.

2. **Understand the Context**: Robert Brown was studying plant cells when he made his discovery. It's important to note that he was particularly interested in the reproductive structures of plants.

3. **Determine the Specific Plant**: Brown discovered the nucleus while examining orchid root cells. This is a crucial detail as it specifies the type of cells he was studying.

4. **Select the Correct Option**: Given the options provided:
- A. Orchid root cells
- B. Bing root cells
- C. May stem cells
- D. Wheat stem cells

The correct answer is option A, as it directly corresponds to the type of cells in which Brown discovered the nucleus.

5. **Conclude the Answer**: Therefore, the nucleus was discovered by Robert Brown in orchid root cells.

### Final Answer:
The nucleus was discovered by Robert Brown in **A. Orchid root cells**.

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