The name of the flower is given to the Phanerogams , to allthe organs of fertilization ( androcea and gynoecium ), whether or not they aresurrounded by floral envelopes ( corolla and calyx , or perianth); if the androeciaor gynoecium is absent, the name of flower is given to the ovary or to theremaining stamens . Finally, by extension, sterile Tesco Flowers are those which are reduced to floral envelopes,either by abortion or by transformation of the organs of fertilization. The flower has the special function of giving birth to the fruit and the seed, i.e.to ensure the reproduction of the species. All parts of the flower, sepals, petals,stamens, carpels, are modified leaves. As for the relative disposition of the various parts of a complete flower, it is given by its diagram.
A flower diagram is called the horizontal projection plane of this flower, ie. Different whorls that compose it. The pieces of these whorls are placed on concentric circumferences, these pals or parts of the calyxon the outermost circumference, the petals or pieces of the corolla on the second circumference, the stamens on the third, or on the third and the fourth,etc., according to the number of whorls which includes the and rocea, and finally the ovary on the innermost circumference.
Diagrams are constructed by drawing planes perpendicular to the axis of the flower or flower bud; rarely a single perpendicular section suffices to have the complete diagram; most often we must practice two sections, one at the level of the ovary, the other at a certain distance, and we superimpose the two sections by making their centers coincide to have the projection of the whole flower on a same horizontal plane.
In selected examples, sepals , the stamens of whorl external and lodges the ovary are on the shelves, the petals and stamens of the inner whorl on inter brains. There may be only one whorl of stamens; the petals and sepals,instead of being alternate, may be opposed, the ovary may for example be trimmer(jocularity) and other pent melic floral whorls, etc., hence diagrams very different type.
We can see that the diagrams make it possible to see at glance the relative arrangement of the different parts of the flower. In addition, the comparison of diagrams of more or less close groups can bring out important affinities. Reciprocally, the known affinities between groups of plants make it possible to complete the diagram of certain flowers by representing the parts that should be there and which have aborted. The diagram obtained directly is called empirical, the completed diagram is the theoretical diagram.
The regular, irregular and asymmetrical flowers naturally correspond to regular (with several planes of symmetry), irregular (with single plane of symmetry: Vicia cracca, for example, asymmetrical (Alchemists, for example) .The regular flowers are still called anthropomorphous,isomorphic irregular flowers.
Finally, besides the types described, there are diagrams with two or six floral pieces per whorl, i.e. Dimers and hexamers; they are rare and we will not insist on it.
The flower is usually borne on a pedicel or peduncle; when it is absent, the flower is called sessile. The pedicel is often enlarged at its upper part, where it forms the receptacle or thalamus, which supports all parts of the flower, just as any branch supports the leaves. This analogy is the clearest when the receptacle has the cylinder-conical form (My sours,Magnolia, etc.); on this axis, more or less stretched, are inserted in the spiral order all the pieces that form the whorls floral, as do alternate leaves on a branch. Elsewhere this receptacle is lowered (some Anemones), or swollen in sphere ( Buttercup ), without the spiral order of insertion of the pieces of the flower is modified; often the receptacle affects the shape of a cone; then the pieces of the periapt are inserted near the base, those of the and rocea and gynaeceum above; it may also happen that the receptacle takes the form of a horizontal plateau (Matthew); at other times it digs into a cupule , but the central portion rises like the bottom of a bottle (many Rosaceae); this centralportion usually carries the gynoecium; the organic summit, raised in the convex receptacle, is lowered when it is hollowed into a cupule.
We cannot insist on all the forms and irregularities of the receptacle; its shape plays an important role in the height of insertion of the different whorls , hence the provisions known as hypogyny (the plane of the and rocea is lower than that of the gynoecium) , perianth and stamens are hypogenous),perigynia (plan of the horizontal receptacle or in cases of concavity of the receptacle implantation of stamens and perianth on the edges of the cup at the same level as the gynoecium worn on the raised central cone) finally epigyny(the and rocea’s plan is higher than that of the gynoecium); it is obvious that we can observe all kinds of transitions from one disposition to another. Let us add that in hypogyny the ovary is said to be superior, that in Epiphany it is said to be inferior.
Rarely a plant bears only one flower; when there are a large number of them, they are born differently on the stem or branches and regrouped differently; this provision has been called inflorescence.
When one or more of these whorls are missing, the Tesco Flowers are said to be incomplete. Quite often, outside the chalice, there is a whorl of green scales or bracts, rather like sepals and forming like an extra chalice; it’s the calicle. All the Tesco Flowers which contain both stamens and a pistil are hermaphrodite; those which contain only stamens are called male flowers, those which contain only the pistil are female flowers; these two kinds of Tesco Flowers are said to be unisexual. When the male and female flowers develop on the same foot, the plant is called monoecism (Birch, Nettle, Hazel, Cucumber, etc.), k