Tapetum is essential for the growth, development, and nutrition of pollen grains. They act as harbingers or successors for the pollen. Secretion of enzyme callose degenerates the tetrad wall and synthesises the pollen kit and trephine, thus binding pollen grain together and helping in the pollination process. It provides the nutrition for the microspores resulting in the synthesis of sporopollenin, which in turn forms the pollen grain wall. It is a specialised layer found within the anther of flowering plants.