Semen and the liquid around the ovum contain substances that nourish, protect, and aid in the development on the embryo. Semen contains enzymes that govern and direct the embryo's developmental process. This process includes the formation of limbs, eyes, and internal organs. Semen also contains high levels of fructose and other simple sugars, which the embryo consumes in the early hours of conception. The liquid surrounding the ovum contains high levels of fats and lipids. These lipids form a protective barrier against pathogens in the mother's body that could be lethal to the embryo.
Yes they play a vital role in providing nutrition to the developing embryo and also acts as a transfer medium for selective absorption and they also act as shock absorbers protetcting the embryo from any physical damage.