Flower structure. Computer artwork showing the main structures of a typical flower. The flower is the reproductive unit of some angiosperm plants. Parts of the flower include one or more carpels (the female reproductive organs), and stamens (the male reproductive organs). The carpels or pistil (the collective term for the carpels) includes an ovary (where the ovules are produced, a style (a tube on top of the ovary), and a stigma (which receives the pollen during fertilisation). The male reproductive part of the flower, the stamen, consists of an anther (which produces pollen) and a filament, which supports the anther.