Archesporium refers to a cell or group of cell from which spore mother cell will develop. Archesporium produces archesporial cells which then develops in to sporogenous tissue. Cells from it develop into gametic cell participating in fertilization process.

Tapetal layer are found around the middle layers of surrounding the sprogenous tissue. Tapetum provides nourishment to sporogenous tissue.

Outermost endosperm layer is the aleurone layer having nutritive function.