Double fertilisation in an angiospermous plant means

Options

A. Fusion of egg cell with male gamete
B. Fusion of secondary nucleus with male gamete
C. Both the above
D. None the above

Answer

### 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 happen simultaneously.

2. **Pollen Tube Formation**:
- When a pollen grain lands on the stigma of a flower, it germinates and forms a pollen tube. This tube grows down through the style and enters the ovule through an opening called the micropyle.

3. **Male Gametes**:
- The pollen tube carries two male gametes (sperm cells) to the ovule.

4. **First Fertilization Event**:
- One of the male gametes fertilizes the egg cell (female gamete). This fusion results in a diploid zygote (2n), which will develop into the embryo.

5. **Second Fertilization Event**:
- The second male gamete fuses with the two polar nuclei present in the central cell of the ovule. This fusion forms a triploid cell (3n), which will develop into the endosperm, providing nourishment to the developing embryo.

6. **Conclusion**:
- Therefore, double fertilization results in the formation of both an embryo (from the fertilization of the egg cell) and endosperm (from the fertilization of the polar nuclei).

7. **Answering the Question**:
- The question asks what double fertilization in angiosperms means. The correct answer includes both the fusion of the egg cell with a male gamete and the fusion of the polar nuclei with a male gamete. Thus, the answer is "both of the above."

### Final Answer:
Double fertilization in an angiospermous plant means the fusion of the egg cell with a male gamete and the fusion of the polar nuclei with another male gamete, resulting in the formation of an embryo and endosperm.