Which one is larger nucleus in pollen grain ?

Options

A. generative nucleus
B. vegetative nucleus
C. male gamete nucleus
D. prothallial nucleus

Answer

### Step-by-Step Solution:

1. **Understanding Pollen Grain Structure**:
- Pollen grains are the male gametophytes in flowering plants and contain the male gametes. They are composed of two main cells: the vegetative cell and the generative cell.

2. **Identifying the Cells**:
- The vegetative cell is larger and contains the vegetative nucleus.
- The generative cell is smaller and contains the generative nucleus.

3. **Comparing Nuclei**:
- The vegetative nucleus, found in the larger vegetative cell, is larger than the generative nucleus, which is found in the smaller generative cell.

4. **Considering Other Options**:
- The male gamete nucleus is derived from the generative cell and is smaller than the vegetative nucleus.
- The prothalial cell and its nucleus are found in gymnosperms and are not present in angiosperms, making them irrelevant to the question.

5. **Conclusion**:
- Based on the information, the largest nucleus in a pollen grain is the vegetative nucleus, which is found in the vegetative cell.

### Final Answer:
The larger nucleus in a pollen grain is the **vegetative nucleus**.

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