Endosperm is formed during the double fertilization by

Options

A. Two polar nuclei & one male gamete
B. One polar nuclei & one male gamete
C. Ovun and male gemete
D. Two polar nuclei & two male gamete

Answer

To solve the question regarding the formation of endosperm during double fertilization, we can break down the process step by step.

### Step-by-Step Solution:

1. **Understanding Double Fertilization**:
- Double fertilization is a unique process that occurs in angiosperms (flowering plants). It involves two fertilization events that take place simultaneously.

2. **Identifying the Components Involved**:
- In double fertilization, there are two main components involved:
- One male gamete (sperm cell).
- Two polar nuclei (which are found in the central cell of the ovule).

3. **Fertilization Events**:
- During double fertilization:
- One male gamete fuses with the egg cell to form the zygote (which develops into the embryo).
- The second fertilization event involves the same male gamete fusing with the two polar nuclei.

4. **Formation of Endosperm**:
- The fusion of one male gamete with the two polar nuclei results in the formation of a triploid nucleus (3n). This triploid nucleus develops into the endosperm, which serves as a food reserve for the developing embryo.

5. **Conclusion**:
- Therefore, the endosperm is formed during double fertilization by the fusion of two polar nuclei and one male gamete.

### Final Answer:
The correct option is **a. two polar nuclei and one male gamete**.

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