Which of the following statement is wrong wrt pollen grain and fertilisation in angiosperms

Options

A. Pollen grain in some plants remains viable for months.
B. Tapetum nourishes the developing pollen.
C. Vegetative cells larger than generative cell.
D. PEN is produced by the fusion of two polar nuclei

Answer

To determine which statement is incorrect regarding pollen grain and fertilization in angiosperms, we can analyze each statement provided in the question.

### Step-by-Step Solution:

1. **Understanding Pollen Viability**:
- Pollen grains can remain viable for varying lengths of time depending on the species. For example, in wheat and rice, the viability is approximately 30 minutes, while in other species (like those in the Rosaceae, Solanaceae, and Leguminosae families), pollen grains can remain viable for months.
- **Conclusion**: The statement regarding pollen viability is correct.

2. **Role of Tapetum**:
- The tapetum is a layer of cells in the microsporangium that provides nourishment to the developing pollen grains. It is essential for the development of pollen grains.
- **Conclusion**: The statement about the tapetum nourishing the developing pollen grain is correct.

3. **Comparison of Vegetative and Generative Cells**:
- In a pollen grain, the vegetative cell is indeed larger than the generative cell. The vegetative cell contains more cytoplasm and has an irregular nucleus, while the generative cell is smaller and spindle-shaped.
- **Conclusion**: The statement that the vegetative cell is larger than the generative cell is correct.

4. **Formation of Primary Endosperm Cell Nucleus**:
- The statement claims that the primary endosperm cell nucleus is formed by the fusion of two polar nuclei. However, this is incorrect. The two polar nuclei (which are haploid) fuse to form a diploid secondary nucleus, which then fuses with a male gamete to form the primary endosperm nucleus.
- **Conclusion**: The statement regarding the formation of the primary endosperm cell nucleus is incorrect.

### Final Answer:
The incorrect statement regarding pollen grain and fertilization in angiosperms is the fourth statement: "primary endosperm cell nucleus is formed by the fusion of two polar nuclei."

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