Trimorphism

Trimorphism

In biology, trimorphism is the existence in certain plants and animals of three distinct forms, especially in connection with the reproductive organs.

In trimorphic plants there are three forms, differing in the lengths of their pistils and stamens, in size and color of their pollen grains, and in some other respects; and, as in each of the tree forms there are two sets of stamens, the three forms possess altogether six sets of stamens and three kinds of pistils. These organs are so proportioned in length to each other that half the stamens in two of the forms stand on a level with the stigma of the third form. To obtain full fertility with these plants, it is necessary that the stigma of the one should be fertilized by pollen taken from the stamens of corresponding height in another form. Hence six unions are legitimate, that is, fully fertile, and 12 are illegitimate, or more or less unfertile. Wallace has shown that the females of certain butterflies from the Malay Archipelago appear in three conspicuously distinct forms without intermediate links.

In crystallography, "trimorphism" refers to the occurrence of certain forms in minerals which have the same chemical composition, but are referable to three systems of crystallization.

ee also

*Sexual dimorphism

References

*Text from "Collier's New Encyclopedia" (1921).


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  • Trimorphism — Tri*mor phism, n. [See {Trimorphic}.] 1. (Crystallog.) The property of crystallizing in three forms fundamentally distinct, as is the case with titanium dioxide, which crystallizes in the forms of rutile, octahedrite, and brookite. See… …   The Collaborative International Dictionary of English

  • trimorphism — [trī môr′fiz΄əm] n. [< Gr trimorphos, of three forms < tri , three + morphē, form + ISM] 1. Crystallography the property of crystallizing in three distinct forms 2. Bot. the existence of three distinct forms of flowers, leaves, or other… …   English World dictionary

  • trimorphism — n. Bot., Zool., & Crystallog. existence in three distinct forms. Derivatives: trimorphic adj. trimorphous adj. * * * (ˈ)trī|mȯrˌfizəm noun ( s) Etymology: International Scientific Vocabulary trimorph (from Greek trimorphos having three forms) +… …   Useful english dictionary

  • trimorphism — n …   Dictionary of invertebrate zoology

  • trimorphism — trimorphic, trimorphous, adj. /truy mawr fiz euhm/, n. 1. Zool. the occurrence of three forms distinct in structure, coloration, etc., among animals of the same species. 2. Bot. the occurrence of three different forms of flowers, leaves, etc., on …   Universalium

  • trimorphism — Existence under three forms, as in holometabolous insects that pass through larval, pupal, and imago stages. [tri + G. morphe, form] …   Medical dictionary

  • trimorphism — tri·mor·phism …   English syllables

  • trimorphism — /traɪˈmɔfɪzəm/ (say truy mawfizuhm) noun 1. Zoology the occurrence of three forms distinct in structure, colouration, etc., among animals of the same species. 2. Crystallography the property of some substances of crystallising in three… …  

  • Heterogonous trimporphism — Trimorphism Tri*mor phism, n. [See {Trimorphic}.] 1. (Crystallog.) The property of crystallizing in three forms fundamentally distinct, as is the case with titanium dioxide, which crystallizes in the forms of rutile, octahedrite, and brookite.… …   The Collaborative International Dictionary of English

  • trimorphic — (ˈ)trī|mȯrfik adjective Etymology: trimorphism + ic : exhibiting trimorphism …   Useful english dictionary

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