Which one forms the endosperm

Options

A. Antipodals
B. Synergids
C. Secondary nucleus
D. Oosphere.

Answer

**Step-by-Step Solution:**

1. **Understanding Double Fertilization**: In angiosperms, a unique process called double fertilization occurs. This involves the fusion of two male gametes with different structures in the female gametophyte.

2. **Role of Male Gametes**: When pollen grains land on the stigma of a flower, they germinate and form a pollen tube that carries two male gametes into the embryo sac.

3. **First Male Gamete**: The first male gamete fuses with the egg cell in the embryo sac. This fusion is known as syngamy and results in the formation of the zygote, which will develop into the embryo.

4. **Second Male Gamete**: The second male gamete does not fuse with the egg; instead, it fuses with the two polar nuclei (also referred to as the secondary nucleus) present in the embryo sac.

5. **Triple Fusion**: The fusion of the second male gamete with the secondary nucleus is called triple fusion. This process leads to the formation of the endosperm, which serves as a nutrient source for the developing embryo.

6. **Conclusion**: Therefore, the endosperm is formed from the fusion of the second male gamete with the secondary nucleus during the process of triple fusion.

**Final Answer**: The secondary nucleus forms the endosperm.

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