User:Dracophyllum/flower
From Wikipedia, the free encyclopedia
A flower, sometimes known as a bloom or a blossom when referring to fruit trees, is the reproductive structure found in flowering plants (angiosperms). The biological function of a flower is to facilitate reproduction, usually by providing a mechanism for the union of sperm with eggs. A typical flower consists of the following parts (listed from outside in): the sepals, which protect the bud; the petals, which attract pollinators; the stamens, which contains the precursor to the male sex cells; and the carpel, which receives them on the stigma and then allows for fertilisation.
![Thumb image](http://upload.wikimedia.org/wikipedia/commons/thumb/a/a5/Flower_poster_2.jpg/640px-Flower_poster_2.jpg)
![Thumb image](http://upload.wikimedia.org/wikipedia/commons/thumb/3/31/Bl%C3%BCten_1.jpg/640px-Bl%C3%BCten_1.jpg)
Pollination, the movement of pollen from the anther to the stigma, can be split into two types: self-pollination and cross-pollination. Self-pollination happens when the pollen from the anther is deposited on the stigma of the same flower, or another flower on the same plant. It 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. This pollination does not require an investment from the plant to provide nectar and pollen as food for pollinators. Cross-pollination is the transfer of pollen from the anther of one flower to the stigma of another flower on a different individual of the same species. Many flowers have evolved to be attractive to animals, so as to cause them to be vectors for the transfer of pollen.
After fertilization, the ovary of the flower develops into fruit containing seeds.
In addition to facilitating the reproduction of flowering plants, flowers have long been admired and used by humans to bring beauty to their environment, and also as objects of romance, ritual, religion, medicine and as a source of food. They have also been used to classify plants taxonomically.