Dear student,
The gynoecium is the innermost whorl in a flower. It consists of pistils, which are considered to be the 'female' part of a flower. The gynoecium produces megaspores which are precursors for the female gametophyte and thus, the female gamete. Gynoecium consists of one or more pistils, which have the following parts:
1. Ovary: It houses the female gametophyte.
2. Style: it is the elongated neck portion.
3. Stigma: it is the sticky receptacle for pollen.
The ovary has ovules in it, where the female gametes are formed and kept until fertilisation.
All the best.
Regards!