A flower, also known as a blossom or bloom, is the reproductive structure of angiosperms (flowering plants), with the purpose of attracting pollinators and producing
botanical fruit and
botanical seeds.
"Basically, each flower consists of a floral axis upon which are borne the essential organs of reproduction (
stamens and
pistils) and usually accessory organs (
sepals and
petals); the latter may serve to both attract pollinating insects and protect the essential organs. The floral axis is a greatly modified stem; unlike vegetative stems, which bear leaves, it is usually contracted, so that the parts of the flower are crowded together on the stem tip, the receptacle. The flower parts are usually arrayed in whorls (or cycles) but may also be disposed spirally, especially if the axis is elongate. There are commonly four distinct whorls of flower parts:
- an outer calyx consisting of sepals; within it lies
- the corolla, consisting of petals
- the androecium, or group of stamens
- the gynoecium, in the center, consisting of the pistils.
The sepals and petals together make up the
perianth, or floral envelope. The sepals are usually greenish and often resemble reduced leaves, while the petals are usually colorful and showy. Sepals and petals that are indistinguishable, as in lilies and tulips, are sometimes referred to as tepals. The androecium, or male parts of the flower, comprise the stamens, each of which consists of a supporting filament and an anther, in which
pollen is produced. The gynoecium, or female parts of the flower, comprises one or more pistils, each of which consists of an
ovary, with an upright extension, the style, on the top of which rests the
stigma, the pollen-receptive surface. The ovary encloses the
ovules, or potential seeds. A pistil may be simple, made up of a single
carpel, or ovule-bearing modified leaf; or compound, formed from several carpels joined together."