Gynoecium

With gynoecium ( sometimes gynaeceum, both of Latinized forms of Ancient Greek γυναικεῖον gynaikeion " women's quarters " ) refers to the totality of the Megasporophylle ( carpels, carpels ) of the flower from seed plants. Carpels bear the ovules, which develop into the embryo sac cell ( megaspore ) and the resulting solid, female gametophyte; after fertilization of the egg cell of the gametophyte, the seed forms (see also: seed plants, generation change ). Components of the gynoecium are involved in the angiosperms in the formation of the fruit. The shape and composition of the gynoecium are important features in assessing the systematic position of plant taxa. The morphology of the gynoecium plays a crucial role in pollination and for the dissemination of seeds and can give information on aspects of the ecology of a plant.

In the angiosperms the carpels are spirally arranged or whorled on the floral axis. The portion of the floral axis with the carpels is located above the insertion of the other floral organs ( androecium, petals, sepals ) surrounding the gynoecium; in some taxa about growing axis tissues of the gynoecium and thus raises the other floral organs on the approach of the gynoecium ( see position of the ovary below). It is believed that original Gynoeceen have assembled from a variety of free-standing carpels. In the course of evolution, have forms with few or only one carpel emerged ( oligomerization ), also Gynoeceen with each other carpels. Gynoeceen with free carpels is called chorikarp or apokarp, Gynoeceen with carpels is called coenokarp.

Apokarpe Gynoeceen, morphology of the carpels

Apokarpe Gynoeceen consist of one or more not among carpels. A apokarpes gynoecium form such as the buttercup family. The carpels of angiosperms are divided into a lower, fertile area with the ovules ( ovary, ovary) and an upper sterile section that represents pen ( stylus), the upper end which serves to hold the pollen grains scar ( stigma ). Carpels are from below congenital tubular fused ( congenital: the coalescence has already been created in the formation of the tissue). A portion of the overlying area grows together post- genital; the interface of the post- genital deformity ( suture ) is visible in the carpels of many taxa. On both sides of the interface are formed inside the carpel the ovules; the tissue from which emerge the ovules is called placenta. At the interface opposite, dorsal side of the carpel and run in the placentas vascular bundles.

Coenokarpe Gynoeceen

In coenokarpen Gynoeceen the carpels are at least partially fused together. A coenokarpes gynoecium possess such as the lily family. Analogous to the individual carpels of the gynoecium apokarpen is called in the coenokarpen Gynoeceen the fertile area with the ovules as ovary and the sterile portion above the ovary as a stylus. Frequently the term punch ( pestle ) used for coenokarpe Gynoeceen. If only the fertile regions of the carpels grow, but the sterile sections are free, is referred to the latter as Stylodien. Stylodien found, for example, in the autumn crocus. When fused to the full length of carpels, the number of stigma lobes can give an indication of the number of carpels involved in the formation of the gynoecium.

In cross section, the ovary can coeno - synkarper Gynoeceen a number of compartments ( loculi, Loculamente ) recognize that correspond to the interiors of the fused carpels. The compartments are separated by septa ( septa ), which are formed by the side surfaces of the adjacent carpels. The placentas with ovules are created in these ovary where the septa meet (central angle constant placentation ). The central body is referred to as such ovary columella.

In coeno - parakarpen ovary no (real) septa are formed, they usually have a ungekammerten indoors. The placentas with ovules sit parietal ( parietal ). In some plants with parakarpen ovary there are invaginations or septa that do not go back to the side faces of carpels, but by growth of placental tissue arise ( "false septa ", eg in some cruciferous plants ).

The ovules of plants with central placentation sit at a free-standing columella or basal or apical to the center of a parakarpen ovary.

Position of the ovary

Is the ovary sunk in the tissue of the floral axis and fused with this, we speak of a inferior ovary (the other floral organs are epigyn ). With superior ovaries (flower hypogynous ), the approach of the ovary is at the flower axis above the attachment points of androecium and corolla or calyx or are free at the bottom of a hypanthium formed by the floral axis ( flower cups, flower perigynous ). Besides occur transitional forms between two extremes on ( " medium-sized " ovary ). Notwithstanding this some authors refer to the ovary, which are free at the bottom of a hypanthium, as "medium constantly " and name the hypanthium partly intergrown ovary " semi- inferior ". In some taxa of the ovary sits on a stalk -like extended portion of the floral axis ( Gynophor ).

Swell

• Sitte, P., Ziegler, H., Ehrendorfer, F., Bresinsky, A. Textbook of Botany at universities. Founded by E. Strasburger. 33rd. G. Fischer Verlag, Stuttgart 1991. 1030 pp. ISBN 3-437-20447-5
• Troll, W. Practical Introduction to plant morphology. An auxiliary directory for the botanical teaching and self-study. Part Two: The flowering plant. VEB Gustav Fischer, Jena 1957. Reprint. ISBN 3-87429-085-9