A flower is a modified shoot of a plant intended for reproduction by seeds. Unlike the usual twigs (shoots), it develops from a flower bud. The stem part of the flower is the pedicel and the flower-root. Corolla, calyx, stamen and pistil are formed by modified leaves. To understand why the plant needs all these organs, it is necessary to study in more detail the structure of any flower. So, in its center there is a pistil, which, despite its name, is a "female" reproductive organ. As a rule, around it are numerous stamens, which are the "male" organ of reproduction. In any flower, the stamen and pestle are its main parts. Of these, a fruit of the plant will subsequently be formed, the seeds of which are a reliable means of reproduction.
The stamen and pestle play a crucial role in the life of flowering plants. The male sexual organ of any flower, representing the totality of all the stamens, is usually called "androceum." Each of them has a "stamen filament" and 4 "pollen sacks", imprisoned in an "anther". It consists of two halves, each of which, in turn, has two more cavities (chambers or nests). They are all known pollen. Water and nutrients are carried along the filaments. The female sexual organ of the flower is the "gynecia", which, in fact, is called the "pestle". It consists of a "column", "ovary" and "stigma". On this "stigma" and gets ripe on stamens pollen. "Column" performs supporting functions, and seeds grow from the "ovary" containing the ovules (one or several), during fertilization. In semyachatkah there are germinal sacs, which quickly develop and form the fruit of the plant. Pestle and stamina, the scheme of which will not be complete without the "nectaries" that emit sweet nectar, most often receive pollen with the help of insects flying from flower to flower. Perianth consists of corolla and calyx. Pestle and stamen are surrounded by perianth.
There are many different types of flowers, which are due to the presence of certain organs. So, plants, in which flowers have pestles and stamens, belong to "bisexual". If there are only stamens or only pistils, the plant is referred to as "dioecious". "Monogamous" refers to those representatives of the flora, on which there are flowers and with stamens, and with pestles. "Dioecious" refers to plants that have only pistillate or only staminate flowers.
The structure of the pistil and staminate was formed over millions of years. The flower is the reproductive organ of all angiosperms. The stamen and pestle provide the plant with the formation of fruits (seeds). The fruit appears in the process of flesh growth. It can be simple (pea, plum, cherry) or complex (consists of several intergrown pestles - carnation, water lily, cornflower). Many representatives of the flora have underdeveloped (rudimentary) pistils. Species diversity in the forms and structure of flowers is associated with the differences in their methods of pollination that arose during the long evolution.