stamen
enUKsta·men
S0699500 (stā′mən)stamen
(ˈsteɪmɛn)sta•men
(ˈsteɪ mən)n., pl. sta•mens, stam•i•na (ˈstæm ə nə)
sta·men
(stā′mən)stamen
| Noun | 1. | stamen - the male reproductive organ of a flower |
| 单词 | stamen | |||
| 释义 | stamenenUKsta·menS0699500 (stā′mən)stamen(ˈsteɪmɛn)sta•men(ˈsteɪ mən)n., pl. sta•mens, stam•i•na (ˈstæm ə nə) sta·men(stā′mən)stamen
stamen(ˈsteimən) nounstamenenUKstamen,one of the four basic parts of a flowerflower,name for the specialized part of a plant containing the reproductive organs, applied to angiosperms only. A flower may be thought of as a modified, short, compact branch bearing lateral appendages. ..... Click the link for more information. . The stamen (microsporophyll), is often called the flower's male reproductive organ. It is typically located between the central pistil and the surrounding petals. A stamen consists of a slender stalk (the filament) tipped by a usually bilobed sac (the anther) in which microspores develop as pollenpollen, minute grains, usually yellow in color but occasionally white, brown, red, or purple, borne in the anther sac at the tip of the slender filament of the stamen of a flowering plant or in the male cone of a conifer. ..... Click the link for more information. grains. The number of stamens is a factor in classifying plant families, e.g., there are 5 (or multiples of 5) in the rose family and 10 in the pulse family. In most flowers the stamens are constructed so as to promote cross-pollination and to avoid self-pollination; e.g., they may be longer than the pistil or may be so placed in relation to the pistil (as in the mountain laurel and the lady's-slipper) as to prevent the pollinating insect from transferring the pollen of a flower to its own pistil. There may be differing maturation times for the stigma of the pistil and for the anther. In some plants there are some flowers (staminate) that bear stamens and no pistil and others (pistillate) that have a pistil and no stamens; these flowers may be borne on the same or on separate plants of the same species. In some highly developed flowers, especially double ones, and in some horticultural varieties (e.g., the geranium) the stamen may be modified into a sterile petallike organ. Stamenthe reproductive organ of the flower of angiosperms in which the pollen grains are formed. The stamen is homologous to the microsporophyll. A typical stamen consists of an anther filament, which contains a vascular bundle, and an anther, the symmetrical halves of which are joined by a strand attached to the anther filament. Microspores are formed from the cells of the archesporium after meiosis. In each of the four nidi of the anther (microsporangia), the microspores sprout into male gametophytes—pollen grains. The aggregate of stamens of a flower is called the androecium. The stamens are arranged on the torus spirally (as in many Ranunculaceae) or in circles. Stamens arranged spirally may range from one to numerous; those arranged in a circle usually number from three to ten. Stamens may concresce with the anthers (Compositae), the filaments (legumes), or entirely (some Cucurbitaceae). They sometimes concresce with other parts of the flower, for example, the corolla (many sympetallous plants) or the pistil (some Orchidaceae). A. N. SLADKOV stamen[′stā·mən]stamenstamenenUKstamenthe male organ in angiosperm flowers, consisting of a stalk, or filament, bearing an anther in which POLLEN grains are produced by MEIOSIS.stamenenUK
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