Most female gametes have two synergids that play a key role during fertilization in more than 80% angiosperms. During the fertiliz ation of angiosperms, the degenerated synergid induces a pollen tube to enter and break the pollen tube to releas e two sperm cells , which fuse with the egg and central cell. In addition, some biological events, such as separating the male germ unit, providing mov ement orbits f or the two sperm cells and inducing boths permto synthesis DNA, may also be related to the degenerated synergid. The structure of both synergids is clear, but the developmental mechanism and the roles during fertilization are not yet understood. The developmental mechanism and physiologic al functions of sy nergid are attractive research topics, and some related new results, especially from molecular biology, provide new clues to probe the synergid functions.