Synergids or helper cells are known as cooperative cells in plants.

These cells generally possess a micropylar nucleus and a chalazal vacuole .The electron microscope studied have revealed that the synergids lack a cell wall on their chalazl side at maturity. They posses filiform apparatus at the micropylar tips. These are finger like projections and comprise a core of microfibrils enclosed in sheath. Synergids start to degenerate  just with pollination.They secrete chemical substance that direct the pollen tube growth inside embryo sac.