Flower - Flowering plants heterosporangiate (producing two types of reproductive spores). The pollen (male spores) and ovules (female spores) are produced in different organs, but the typical flower is a bisporangiate strobilus in that it contains both organs. A flower is regarded as a modified stem (Eames, 1961) with shortened internodes and bearing, at its nodes, structures that may be highly modified leaves. In essence, a flower structure forms on a modified shoot or axis with an apical meristem that does not grow continuously (growth is determinate). The stem is called a pedicel, the end of which is the torus or receptacle. The parts of a flower are arranged in whorls on the torus.