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Dimorphism (other)
Dimorphism or dimorphic may refer to: Science * Dimorphic root systems, plant roots with two distinctive forms for two separate functions * Sexual dimorphism, a phenotypic difference between males and females of the same species * Nuclear dimorphism, when a cell's nuclear apparatus is composed of two structurally and functionally differentiated types of nuclei * Frond dimorphism, differing forms of fern fronds between the sterile and fertile fronds * Phenotypic dimorphism, switching between two cell-types ** Dimorphic fungi, fungi which undergo this type of switching * Dimorphism (geology), the property of some substances to exist in two distinct crystalline forms Mathematics * Semilinear map, a homomorphism between modules, paired with the associated homomorphism between the respective base rings See also * Polymorphism (other) * Monomorphic (other) Monomorphic or Monomorphism may refer to: *Monomorphism, an injective homomorphism in mathematics * Monomorph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimorphic Root System
A dimorphic root system is a plant root system with two distinct root forms, which are adapted to perform different functions. One of the most common manifestations is in plants with both a taproot, which grows straight down to the water table, from which it obtains water for the plant; and a system of lateral roots Lateral roots, emerging from the pericycle (meristematic tissue), extend horizontally from the primary root (radicle) and over time makeup the iconic branching pattern of root systems. They contribute to anchoring the plant securely into the soil, ..., which obtain nutrients from superficial soil layers near the surface. Many plants with dimorphic root systems adapt the levels of rainfall in the surrounding area, growing many surface roots when there is heavy rainfall, and relying on a taproot when rain is scarce. Because of their adaptability to water levels in the surrounding area, most plants with dimorphic root systems live in arid climates with common wet and dry pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most animals and some plants. Differences may include secondary sex characteristics, size, weight, colour, markings, or behavioural or cognitive traits. These differences may be subtle or exaggerated and may be subjected to sexual selection and natural selection. The opposite of dimorphism is ''monomorphism'', which is when both biological sexes are phenotypically indistinguishable from each other. Overview Ornamentation and coloration Common and easily identified types of dimorphism consist of ornamentation and coloration, though not always apparent. A difference in coloration of sexes within a given species is called sexual dichromatism, which is commonly seen in many species of birds and reptiles. Sexual selection leads to the exaggerated dim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear Dimorphism
Nuclear dimorphism is a term referred to the special characteristic of having two different kinds of nuclei in a cell. There are many differences between the types of nuclei. This feature is observed in protozoan ciliates, like ''Tetrahymena'', and some foraminifera. Ciliates contain two nucleus types: a macronucleus that is primarily used to control metabolism, and a micronucleus which performs reproductive functions and generates the macronucleus. The compositions of the nuclear pore complexes help determine the properties of the macronucleus and micronucleus. Nuclear dimorphism is subject to complex epigenetic controls. Nuclear dimorphism is continuously being studied to understand exactly how the mechanism works and how it is beneficial to cells. Learning about nuclear dimorphism is beneficial to understanding old eukaryotic mechanisms that have been preserved within these unicellular organisms but did not evolve into multicellular eukaryotes. Key components The ciliated prot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Frond Dimorphism
Frond dimorphism refers to a difference in ferns between the fertile and sterile fronds. Since ferns, unlike flowering plants, bear spores on the leaf blade itself, this may affect the form of the frond itself. In some species of ferns, there is virtually no difference between the fertile and sterile fronds, such as in the genus ''Dryopteris'', other than the mere presence of the sori, or fruit-dots, on the back of the fronds. Some other species, such as ''Polystichum acrostichoides'' (Christmas fern), or some ferns of the genus ''Osmunda'', feature dimorphism on a portion of the frond only. Others, such as some species of ''Blechnum'' and ''Woodwardia'', have fertile fronds that are markedly taller than the sterile. Still others, such as ''Osmunda cinnamomea'' (Cinnamon fern), or plants of the family Onocleaceae, have fertile fronds that are completely different from the sterile. Only members of the ''Onocleaceae'' and ''Blechnaceae'' exhibit a propensity towards dimorphy, while ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenotypic Dimorphism
Phenotypic switching is switching between multiple cellular morphologies. David R. Soll described two such systems: the first high frequency switching system between several morphological stages and a second high frequency switching system between opaque and white cells. The latter is an epigenetic switching system Phenotypic switching in ''Candida albicans'' is often used to refer to the epigenetic white-to-opaque switching system. ''C. albicans'' needs this switch for sexual mating. Next to the two above mentioned switching systems many other switching systems are known in ''C. albicans''. A second example occurs in melanoma, where malignantly transformed pigment cells switch back-and-forth between phenotypes of proliferation and invasion in response to changing microenvironments, driving metastatic progression. See also *Polyphenism A polyphenic trait is a trait for which multiple, discrete phenotypes can arise from a single genotype as a result of differing environmental c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimorphic Fungi
Dimorphic fungi are fungi that can exist in the form of both mold and yeast. This is usually brought about by change in temperature and the fungi are also described as thermally dimorphic fungi. An example is ''Talaromyces marneffei'', a human pathogen that grows as a mold at room temperature, and as a yeast at human body temperature. The term dimorphic is commonly used for fungi that can grow both as yeast and filamentous cells, however many of these dimorphic fungi actually can grow in more than these two forms. Dimorphic is thus often used as a general reference for fungi being able to switch between yeast and filamentous cells, but not necessary limiting more shapes. Ecology of dimorphic fungi Several species of dimorphic fungi are important pathogens of humans and other animals, including ''Coccidioides immitis'', ''Paracoccidioides brasiliensis'', ''Candida albicans'', ''Blastomyces dermatitidis'', ''Histoplasma capsulatum'', ''Sporothrix schenckii'', and ''Emmonsia'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimorphism (geology)
In materials science, polymorphism describes the existence of a solid material in more than one form or crystal structure. Polymorphism is a form of isomerism. Any crystalline material can exhibit the phenomenon. Allotropy refers to polymorphism for chemical elements. Polymorphism is of practical relevance to pharmaceuticals, agrochemicals, pigments, dyestuffs, foods, and explosives. According to IUPAC, a polymorphic transition is "A reversible transition of a solid crystalline phase at a certain temperature and pressure (the inversion point) to another phase of the same chemical composition with a different crystal structure." According to McCrone, polymorphs are "different in crystal structure but identical in the liquid or vapor states." Materials with two polymorphs are called dimorphic, with three polymorphs, trimorphic, etc. Examples Many compounds exhibit polymorphism. It has been claimed that "every compound has different polymorphic forms, and that, in general, the num ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semilinear Map
In linear algebra, particularly projective geometry, a semilinear map between vector spaces ''V'' and ''W'' over a field ''K'' is a function that is a linear map "up to a twist", hence ''semi''-linear, where "twist" means "field automorphism of ''K''". Explicitly, it is a function that is: * additive with respect to vector addition: T(v+v') = T(v)+T(v') * there exists a field automorphism ''θ'' of ''K'' such that T(\lambda v) = \lambda^\theta T(v), where \lambda^\theta is the image of the scalar \lambda under the automorphism. If such an automorphism exists and ''T'' is nonzero, it is unique, and ''T'' is called ''θ''-semilinear. Where the domain and codomain are the same space (i.e. ), it may be termed a semilinear transformation. The invertible semilinear transforms of a given vector space ''V'' (for all choices of field automorphism) form a group, called the general semilinear group and denoted \operatorname(V), by analogy with and extending the general linear group. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymorphism (other)
Polymorphism, polymorphic, polymorph, polymorphous, or polymorphy may refer to: Computing * Polymorphism (computer science), the ability in programming to present the same programming interface for differing underlying forms * Ad hoc polymorphism, applying polymorphic functions to arguments of different types * Parametric polymorphism, abstracts types, so that multiple can be used with a single implementation ** Bounded quantification, restricts type parameters to a range of subtypes * Subtyping, different classes related by some common superclass can be used in place of that superclass * Row polymorphism, uses structural subtyping to allow polymorphism over records * Polymorphic code, self-modifying program code designed to defeat anti-virus programs or reverse engineering Science Biology * Chromosomal polymorphism, a condition where one species contains members with varying chromosome counts or shapes * Cell polymorphism, variability in size of cells or nuclei * Gene polymorph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
