Asexual system is a distribution ofmale andfemale functions acrossorganisms in aspecies.[1][2] The termsreproductive system andmating system have also been used as synonyms.[3]
Male (a.k.a. staminate) flowers have astamen but nopistil and produce only male gametes. Female (a.k.a. pistillate) flowers only have a pistil. Hermaphrodite (a.k.a. perfect, or bisexual) flowers have both a stamen and pistil. The sex of a single flower may differ from the sex of the whole organism: for example, a plant may have both staminate and pistillate flowers, making the plant as a whole a hermaphrodite. Hence although all monomorphic plants are hermaphrodites, different combinations of flower types (staminate, pistillate, or perfect) produces distinct monomorphic sexual systems.[8]
rare sexual system inangiosperms, in which a plant has both male and hermaphroditic flowers.[13] It has been a subject of interest regarding the mechanism of sex expression.[14]
an individual plant produces either exclusively male or exclusively female flowers at different points in time.[15] It is thought the temporal separation of producing male and female flowers occurs to prevent self-fertilization,[16] however this is debatable as dichogamy occurs in similar frequency among species which are self-compatible and self-incompatible.[17]
a species has distinct individual organisms that are either male or female, i.e., they produce only male or only female gametes, either directly (in animals) or indirectly (in plants).[20]
The term "gonochorism" is usually applied to animals while "dioecy" is applied to plants.[21] Gonochorism is the most common sexual system in animals, occurring in 95% of animal species.[22]
defined as the presence of bothfemale andhermaphrodite flowers on the same individual of a plant species.[23] It is prevalent inAsteraceae but is poorly understood.[24]
Gynodioecy-Gynomonoecy
a sexual system for plants when female, hermaphrodite, and gynomonoecious plants coexist in the same population.[25]: 360
a sexual system in which male and female flowers are present on the same plant. It is common inangiosperms,[26] and occurs in 10% of all plant species.[27][dubious –discuss]
individuals start their adult lives as one sex, and change to the other sex at a later age.[28]
Sequential monoecy
a confusing sexual system,[29] in which the combination of male, female, and hermaphrodite flowers presented changes over time.[30] For example, some conifers produce exclusively either male or female cones when young, then both when older.[31] Sequential monoecy can be difficult to differentiate from dioecy.[32] Several alternative terms may be used in reference to sexual systems involving temporal changes to sex presentation of a plant species (e.g. dichogamy, sequential hermaphroditism, sex change, paradioecy, diphasy).[33]
an individual can produce both gamete types in the same breeding season.[34] Simultaneous hermaphroditism is one of the most common sexual systems in animals (though far less common thangonochorism) and is one of the most stable.[35]
Synoecy
all individuals in a population of flowering plants bear solely hermaphrodite flowers.[28]
males, females, and hermaphrodites exist in the same population.[9] It is present in both plants and animals but is always extremely rare.[36] Trioecy occurs in about 3.6% of flowering plants.[37] Trioecy may infrequently be referred to as tridioecy.[38]
^Goldberg EE, Otto SP, Vamosi JC, Mayrose I, Sabath N, Ming R, Ashman TL (April 2017). "Macroevolutionary synthesis of flowering plant sexual systems".Evolution; International Journal of Organic Evolution.71 (4):898–912.doi:10.1111/evo.13181.PMID28085192.S2CID19562183.
^Bernstein H, Byerly HC, Hopf FA, Michod RE (September 1985). "Genetic damage, mutation, and the evolution of sex". Science. 229 (4719). New York, N.Y.: 1277–81. Bibcode:1985Sci...229.1277B. doi:10.1126/science.3898363. PMID 3898363.
^Greenwood, Paul J.; Greenwood, Greenwood, Paul John; Harvey, Paul H.; Harvey, Reader in Biology Department of Zoology Paul H.; Slatkin, Montgomery; Slatkin, Professor of Integrative Biology Montgomery; Cambridge, University of (1985-07-11).Evolution: Essays in Honour of John Maynard Smith. CUP Archive. p. 240.ISBN978-0-521-25734-3.{{cite book}}: CS1 maint: multiple names: authors list (link)
