Polar nuclei fuse to produce

Options

A. Diploid secondary nucleus
B. Zygote
C. Antipodals
D. Synergids

Answer

To solve the question "Polar nuclei fuse to produce," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Context**:
- Polar nuclei are found in the embryo sac of angiosperms (flowering plants).
- There are typically two polar nuclei present in the central cell of the embryo sac.

2. **Fusion of Polar Nuclei**:
- The two polar nuclei, each having a haploid (N) ploidy, will fuse together.
- This fusion results in the formation of a diploid (2N) nucleus, known as the secondary nucleus.

3. **Role of the Secondary Nucleus**:
- The diploid secondary nucleus is important as it will later participate in the process of fertilization.
- Specifically, this secondary nucleus will fuse with a second male gamete during the process known as triple fusion.

4. **Formation of Primary Endosperm Cell**:
- The fusion of the diploid secondary nucleus with the second male gamete results in the formation of a triploid (3N) primary endosperm cell.
- This primary endosperm cell will eventually develop into the endosperm, which serves as a nutritive tissue for the developing embryo.

5. **Conclusion**:
- Therefore, the polar nuclei fuse to produce a diploid secondary nucleus, which is the initial answer to the question.

### Final Answer:
The polar nuclei fuse to produce a **diploid secondary nucleus**.

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