What is the function of filiform apparatus in an angiospermic embryo sac ?

Options

A. Brings about opening of the pollen tube
B. Guids the pollen tube into a synergid
C. Prevents entry of more than one pollen tube into a synergid
D. None of these

Answer

### Step-by-Step Solution:

1. **Understanding the Embryo Sac Structure**: The angiospermic embryo sac is a female gametophyte that contains several important cells, including three antipodal cells, two synergid cells, and one egg cell.

2. **Identifying the Filiform Apparatus**: The filiform apparatus is a specialized structure found on the synergid cells of the embryo sac. It consists of elongated, finger-like projections.

3. **Function of the Filiform Apparatus**: The primary function of the filiform apparatus is to guide the pollen tube towards the egg cell. When pollen lands on the stigma, it germinates and forms a pollen tube that grows down through the style to reach the ovule.

4. **Mechanism of Guidance**: The filiform apparatus helps in directing the pollen tube to the micropylar end of the embryo sac, ensuring that it reaches the synergids and the egg cell efficiently. This guidance is crucial for the successful fertilization process.

5. **Conclusion**: Therefore, the function of the filiform apparatus in an angiospermic embryo sac is to guide the pollen tube to the synergids, facilitating the delivery of male gametes for fertilization.