Carpels : Gynoecium :: Stamens : ………………………..

Gynoecium:

1. The innermost whorl of flowers is the gynoecium.
2. Gynoecium refers to the whorl of carpels, the female reproductive part of flowers.
3. A stamen is composed of three parts; stigma, style and ovary.

Androecium:

1. The androecium is the whorl of male reproductive units called stamens.
2. The stamen is composed of two parts: filament and anther.

Carpels are collectively called gynoecium and stamens are collectively called androecium.