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Or, with bisexual and at least one of male and female flowers on the same plant. [2] Protandrous: (of dichogamous plants) having male parts of flowers developed before female parts, e.g. having flowers that function first as male and then change to female or producing pollen before the stigmas of the same plant are receptive. [6]
Female (left) and male (right) Argiope appensa, displaying typical sexual differences in spiders, with dramatically smaller males Hammock Spiders (Pityohyphantes sp.) courting. Female left and male right. Many arachnid groups exhibit sexual dimorphism, [45] but it is most widely studied in the spiders.
In monomorphic sexual systems, a combination of hermaphrodite, male, and/or female flowers may be present on the same plant. Monomorphic sexual systems include monoecy, gynomonoecy, andromonoecy, and trimonoecy. In dimorphic sexual systems, individual plants within a species only produce one sort of flower, either hermaphrodite or male, or female.
In some species of plants, the flowers are imperfect or unisexual: having only either male (stamen) or female (carpel) parts. If unisexual male and female flowers appear on the same plant, the species is called monoecious. [27] However, if an individual plant is either female or male, the species is called dioecious.
In plants, male reproductive structures include stamens in flowering plants, which produce pollen. [3] Female reproductive structures, such as pistils in flowering plants, produce ovules and receive pollen for fertilization. [4] Mosses, ferns, and some similar plants have gametangia for reproductive organs, which are part of the gametophyte. [5]
Male and female flowers evolve from hermaphroditic flowers [19] via andromonoecy or gynomonoecy. [20]: 148 In amaranths monoecy may have evolved from hermaphroditism through various processes caused by male sterility genes and female fertility genes. [20]: 150 Monoecy may be an intermediate state between hermaphroditism and dioecy. [21]
About 94% of flowering plant species are either hermaphroditic (all flowers produce both male and female gametes) or monoecious, where both male and female flowers occur on the same plant. There are also mixed breeding systems , in both plants and animals, where hermaphrodite individuals coexist with males (called androdioecy ) or with females ...
Autoicous – produces male and female sex organs on the same plant but on separate inflorescences. Bract – leaf is present below the flower. Cladautoicous – male and female inflorescences are on separate branches of the same plant. Dioicous – having two forms of gametophyte, one form bearing antheridia and one form bearing archegonia.