Plant reproductive morphology is asexual, producing only spores. Similarly, flowers produced by the sporophyte may be described as "unisexual" or "bisexual", meaning that they give rise to either one sex of gametophyte or both sexes of gametophyte. The flower is the characteristic structure concerned with sexual reproduction in flowering plants (angiosperms). Flowers vary enormously in their construction (morphology). A "complete" flower, like that of "Ranunculus glaberrimus" shown in the figure, has a calyx of outer sepals and a corolla of inner petals. The sepals and petals together form the perianth. Next inwards there are numerous stamens, which produce pollen grains, each containing a
Lithophragma heterophyllum and usually divided into about three pointed lobes. Lithophragma heterophyllum Lithophragma heterophyllum is a species of flowering plant in the saxifrage family known by the common name hillside woodland star. It is native to the coastal mountain ranges of California, where it can generally be found in shady habitat. It is a rhizomatous perennial herb growing erect or leaning with a slender naked flowering stem. The leaves are located on the lower part of the stem, each divided into rounded lobes. The stem bears 3 to 12 flowers, each in a cuplike calyx of red or green sepals. The five