Filiform apparatus is a characteristic feature of:

Explanation

The filiform apparatus is a mass of finger-like projections of the wall into the cytoplasm. It is present in synergids (help cells) of the embryo sac, in the micropylar region. It guards the pollen tube inside the ovule towards the embryo sac. A special cellular thickening present in the synergids at the micropylar end is called filiform apparatus. After fertilization when the egg cell gives rise to a zygote, they get disorganized. The major function is to guide the entry of pollen tubes into synergids and to release sperm cells.