In angiosperms (flowering plants), the ovule is a structure that will eventually develop into a seed after fertilization. It is equivalent to the megasporangium, which is the part of the plant where the megaspores are produced. The megasporangium contains the megaspore mother cell, which undergoes meiosis to produce megaspores.
Thus, the ovule in angiosperms is technically equivalent to the megasporangium, which houses the megaspore mother cell and undergoes processes leading to the formation of seeds.
Sexual reproduction entails a complex life cycle. It comprises a set of events that are divided into the following three stages: