pleomorphism
/pli:ə'mɔ:fizm/
Học thuậtThân thiện
Definition
- Noun:
- (Biology): The occurrence of two or more distinct morphological forms or stages in the life cycle of an organism, or within a single species.
- (Chemistry, Crystallography): The property of a substance, especially a chemical compound, to crystallize in two or more distinct forms with different structures.
Examples of Usage
Noun (Biology):
- The pleomorphism of certain fungi makes them difficult to classify.
- Scientists studied the bacterial pleomorphism under different environmental conditions.
Noun (Chemistry):
- The pleomorphism of carbon is demonstrated by graphite and diamond.
- Calcium carbonate exhibits pleomorphism, forming crystals of both calcite and aragonite.
Advanced Usage
"Genetic pleomorphism": Refers to variations in form linked to genetic differences within a population.
- The genetic pleomorphism in the insect population was linked to its rapid adaptation.
"Pathological pleomorphism": Used in medicine, particularly histology, to describe significant variation in the size and shape of cells or nuclei, often associated with malignancy.
- The pathologist noted marked nuclear pleomorphism in the tumor cells.
Variants and Related Words
Pleomorphic (adj): Having the quality of pleomorphism; existing in various forms.
- The virus is pleomorphic, lacking a consistent shape.
Polymorphism (n): A related but broader term. In biology, it refers to the occurrence of different forms among members of a population or species. In materials science, it is synonymous with pleomorphism for crystalline solids.
- Single nucleotide polymorphism is a common form of genetic variation.
Synonyms
- (Biology): Polymorphism, morphological variation.
- (Chemistry): Allotropy (specifically for elements), polymorphism.
Notes on Meaning
- The term is highly specialized to scientific contexts, primarily biology and chemistry.
- In biology, it can describe normal life cycle stages (e.g., a jellyfish's polyp and medusa forms) or abnormal cellular variation.
- In chemistry, it is a specific case of the more general term "polymorphism," which applies to any crystalline material.
Noun
- (biology) the appearance of two or more distinctly different forms in the life cycle of some organisms
- (chemistry) the existence of different kinds of crystal of the same chemical compound