In a pollen grain, larger nucleus is

Options

A. Generative nucleus
B. Tube nucleus
C. Vegetative nucleus
D. None of these

Explanation

To answer the question "In a pollen grain, the larger nucleus is:", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Composition of Pollen Grains**:
- Pollen grains are microspores found in flowering plants, specifically angiosperms. Each pollen grain typically contains two nuclei.

2. **Identify the Nuclei Present**:
- The two nuclei present in a pollen grain are the generative nucleus and the tube nucleus.

3. **Function of Each Nucleus**:
- The **tube nucleus** is responsible for guiding the growth of the pollen tube, which is essential for fertilization.
- The **generative nucleus** divides to form two sperm cells that will eventually fertilize the egg cell.

4. **Determine the Size of Each Nucleus**:
- In terms of size, the tube nucleus is generally larger than the generative nucleus.

5. **Conclusion**:
- Therefore, the larger nucleus in a pollen grain is the **tube nucleus**.

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

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