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Heteromorphosis (/ ˌhɛt.ə.rəʊˈmɔrf.ə.sɪs /, / ˌhɛt.rə.-/) (Greek: έτερος – other; morphe – form) refers to situations where an organ or tissue is different from the expected, [1] either because of (embryonic) development anomalies, or after reparative regeneration following a trauma. [2]
The morph phenotype is genetically linked to genes responsible for a unique system of self-incompatibility, termed heteromorphic self-incompatibility, that is, the pollen from a flower on one morph cannot fertilize another flower of the same morph. Heterostylous plants having two flower morphs are termed "distylous".
A distinct SI mechanism exists in heterostylous flowers, termed heteromorphic self-incompatibility. This mechanism is probably not evolutionarily related to the more familiar mechanisms, which are differentially defined as homomorphic self-incompatibility .
Alternation of generations in a species which is heteromorphic, sporophytic, oogametic, dioicous, heterosporic and dioecious Plant life cycles can be complex. Alternation of generations can take place in plants which are at once heteromorphic, sporophytic, oogametic, dioicous, heterosporic and dioecious, such as in a willow tree (as most ...
Distyly is a type of heterostyly in which a plant demonstrates reciprocal herkogamy.This breeding system is characterized by two separate flower morphs, where individual plants produce flowers that either have long styles and short stamens (L-morph flowers), or that have short styles and long stamens (S-morph flowers). [1]
However, heteromorphic sex chromosomes are relatively rare, with only five species known as of 2014. Five of these use an XY system, and one (Ginkgo biloba) uses a WZ system. Some gymnosperms, such as Johann's Pine (Pinus johannis), have homomorphic sex chromosomes that are almost indistinguishable through karyotyping. [16]
In stramenopiles: some brown algae (the Fucales, however, their life cycle can also be interpreted as strongly heteromorphic-diplohaplontic, with a highly reduced gametophyte phase, as in the flowering plants), [16] some xanthophytes (e.g., Vaucheria), [17] most diatoms, [12] some oomycetes (e.g., Saprolegnia, Plasmopara viticola), [8] [9 ...
The non-fertilising morph(s) have no function, and are simply developmental errors. This is thought to be unlikely in many sperm heteromorphic species because the production of infertile sperm may be highly regulated, and infertile sperm can make up >90% of the total sperm in some Lepidoptera and Drosophila.