Each carpel consists of a stigma, which receives pollen, a style, which acts as a stalk, and an ovary, which contains the ovules. The gynoecium, or the carpels, is the female part of the flower found on the innermost whorl. In general there is only one type of stamen, but there are plant species where the flowers have two types a "normal" one and one with anthers that produce sterile pollen meant to attract pollinators. Stamens range in number, size, shape, orientation, and in their point of connection to the flower. Although they exhibit the widest variation among floral organs, the androecium is usually confined just to one whorl and to two whorls only in rare cases. The anther contains microsporocytes which become pollen, the male gametophyte, after undergoing meiosis. Stamens consist typically of an anther, made up of four pollen sacs arranged in two thecae, connected to a filament, or stalk. The androecium, or stamens, is the whorl of pollen-producing male parts. 1. Stigma, 2. Style, 3. Stamens, 4. Filament, 5. Petal Androecium Main article: Plant reproductive morphology Reproductive parts of Easter Lily ( Lilium longiflorum). The early word for flower in English was blossom, though it now refers to flowers only of fruit trees. It comes originally from the Latin name of the Italian goddess of flowers, Flora. After fertilization, the ovary of the flower develops into fruit containing seeds.įlowers have long been appreciated by humans for their beauty and pleasant scents, and also hold cultural significance as religious, ritual, or symbolic objects, or sources of medicine and food.įlower is from the Middle English flour, which referred to both the ground grain and the reproductive structure in plants, before splitting off in the 17th century. In this way, many flowering plants have co-evolved with pollinators to be mutually dependent on services they provide to one another-in the plant's case, a means of reproduction in the pollinator's case, a source of food. Most flowering plants depend on animals, such as bees, moths, and butterflies, to transfer their pollen between different flowers, and have evolved to attract these pollinators by various strategies, including brightly colored, conspicuous petals, attractive scents, and the production of nectar, a food source for pollinators. Flowers contain sporangia and are the site where gametophytes develop. Some flowers produce diaspores without fertilization ( parthenocarpy). This pollination does not require an investment from the plant to provide nectar and pollen as food for pollinators. Self-pollination happens in flowers where the stamen and carpel mature at the same time, and are positioned so that the pollen can land on the flower's stigma. Some flowers may self-pollinate, producing seed using pollen from the same flower or a different flower of the same plant, but others have mechanisms to prevent self-pollination and rely on cross-pollination, when pollen is transferred from the anther of one flower to the stigma of another flower on a different individual of the same species. When pollen from the anther of a flower is deposited on the stigma, this is called pollination. The "male" gametophyte, which produces non-motile sperm, is enclosed within pollen grains the "female" gametophyte is contained within the ovule. Flowers produce gametophytes, which in flowering plants consist of a few haploid cells which produce gametes. For other uses, see Floral (disambiguation).Ī flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae).
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