The hypocotyl elongates while the epicotyl remains the same in length. Lengthening of the epicotyl is thought to be controlled by the phytochrome photoreceptors. Dicot seedlings grown in the light develop short hypocotyls and open cotyledons exposing the epicotyl. In this way, the epicotyl pushes the plumule above the ground. An epicotyl is important for the beginning stages of a plant's life. In plant physiology, the epicotyl is the embryonic shoot above the cotyledons. The epicotyl remains dormant until the GA3/ABA ratio is sufficiently different. In most plants the epicotyl will eventually develop into the leaves of the plant.