The fusion product of secondary nucleus and male gamete is

Options

A. Nucellus
B. Primary endosperm nucleus
C. Zygote
D. Secondary nucleus

Answer

**Step-by-Step Solution:**

1. **Understanding the Components:**
- In flowering plants, the male gamete is contained within the pollen grain. When the pollen grain germinates, it forms a pollen tube that carries the male gametes to the ovule.

2. **Pollen Tube Formation:**
- The pollen tube grows towards the ovule, and during this process, the pollen grain divides to produce two male nuclei.

3. **Fertilization Process:**
- One of the male nuclei fuses with the egg cell, resulting in the formation of the zygote, which will develop into the embryo.
- The second male nucleus fuses with the two polar nuclei located in the center of the embryo sac, which is known as the secondary nucleus.

4. **Formation of Primary Endosperm Nucleus:**
- The fusion of the second male nucleus with the secondary nucleus results in the formation of a new cell called the primary endosperm nucleus (PEN). This structure is crucial for the development of the endosperm, which provides nourishment to the developing embryo.

5. **Conclusion:**
- Therefore, the fusion product of the secondary nucleus and the male gamete is the primary endosperm nucleus.

**Final Answer:**
The fusion product of the secondary nucleus and male gamete is the primary endosperm nucleus.

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