Another key term is carpel. Carpels are the building blocks of a pistil. The gynoecium may have one pistil or more. A pistil may have one carpel or more than one stuck together ("fused"). Carpels and pistils have three parts: a stigma at the top where the pollen lands; a style and an ovary. In the case of a pistil, the stigma, style, and ovary may be made up of those parts of more than one carpel, fused.