The filiform apparatus is a structure found within the synergid cells of plant ovules, specifically playing a role in pollen tube guidance and attraction during fertilization.
Composition and Function
According to Chamberlain, the filiform apparatus:
- Consists of cellulose: This highlights its structural component.
- Function seems to be separation of a chemotactic glucose-containing substance: This substance attracts the pollen tube.
- Facilitates Pollen Tube Entry: This process occurs through the micropyle.
Detailed Explanation
The filiform apparatus, located in the synergid cells, projects into the embryo sac. Its primary role is to guide the pollen tube to the egg cell for fertilization. Here's a breakdown:
- Chemotactic Attraction: The filiform apparatus secretes chemical signals (containing glucose) that attract the pollen tube.
- Pollen Tube Guidance: These signals direct the pollen tube towards the ovule through the micropyle, a small opening.
- Synergid Cell Role: The synergid cells, with the filiform apparatus, play a crucial role in the fertilization process. They act as guides, ensuring that the pollen tube reaches its destination.
Summary
In summary, the filiform apparatus is a key structure in plant reproduction, composed of cellulose and responsible for attracting and guiding the pollen tube to the egg cell by secreting chemotactic substances.
