acrosome /ak″rəsōm′/ [Gk, akron + soma, body] , the caplike structure surrounding the anterior end of the head of a spermatozoon. It is derived from the Golgi apparatus within the cytoplasm and contains degradative enzymes that function in the penetration of the ovum during fertilization. Also called acrosomal cap, acrosomal head cap. See also acrosomal reaction. −acrosomal, adj.
