The process of nuclear fusion to form zygote is called..........

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the name of the process that involves nuclear fusion to form a zygote in flowering plants.

2. **Identifying Key Components**: In flowering plants, the female gametophyte is known as the embryo sac. Within the embryo sac, there are specific cells involved in the fertilization process.

3. **Components of the Embryo Sac**: The embryo sac contains:
- **Polar nuclei** located in the central cell.
- **Egg cell** and **synergids** at the micropyle end.
- **Antipodal cells** at the chalazal end.

4. **Fertilization Process**: During fertilization, two male gametes enter the embryo sac through the micropyle:
- One male gamete fuses with the egg cell to form the zygote.
- The other male gamete fuses with the polar nuclei in the central cell.

5. **Naming the Process**: The fusion of the male gamete with the egg cell to form the zygote is specifically referred to as **syngamy**.

6. **Conclusion**: Therefore, the answer to the question is that the process of nuclear fusion to form a zygote is called **syngamy**.

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