Polymorphism, in biology, a discontinuous genetic variation resulting in the occurrence of several different forms or types of individuals among the members of a single species. A discontinuous genetic variation divides the individuals of a population into two or more sharply distinct forms. The most obvious example of this is the separation of higher organisms into male and female sexes. Another example is the different blood types in humans. In continuous variation, by contrast, the individuals do not fall into sharp classes but instead are almost imperceptibly graded between wide extremes. Examples include the smooth graduation of height among individuals of human populations and the graduations possible between the different geographic races. If the frequency of two or more discontinuous forms within a species is too high to be explained by mutation, the variation—as well as the population displaying it—is said to be polymorphic. A polymorphism that persists over many generations is usually maintained because no one form possesses an overall advantage or disadvantage over the others in terms of natural selection. Some polymorphisms have no visible manifestations and require biochemical techniques to identify the differences that occur between the chromosomes, proteins, or DNA of different forms. The castes that occur in social insects are a special form of polymorphism that is attributable to differences in nutrition rather than to genetic variations.
Last Updated on: Nov 23, 2024List of Open Access Journals View More
Department of Electrical Engineering: Current Research
DEECR welcomes authors to contribute current research and reports, Experimental studies, Review articles, Short communication, Editorial, Letter to Editor, Survey Reports submission of manuscripts related to Signal Processing, Material Science, Microelectronics, Electronic materials, Power System Protection, DC Power Converter, C Power Converter, Electrophysics and its applications, Electromagnetism, etc....View More
Reviews in Pharmacy and Pharmaceutical Sciences
Reviews in Pharmacy and Pharmaceutical sciences is a peer-reviewed scholarly journal that aims to publish high quality research on Pharmacology and Toxicology, Pharmaceutical Chemistry, Pharmaceutical Analysis and Quality Assurance, Pharmaceutics, Hospital and Clinical Pharmacy...View More
Department of Applied Food and Nutrition Journal
DAFNJ is a scholarly open access peer-reviewed journal aim to publish be valuable source of information both clinical, experimental and theoretical in field of Food science, Food policy and Nutrition....View More
International Journal of Biomaterials and Tissue Engineering
IJBTE is a scholarly open access peer-reviewed journal aim to publish be valuable source of information both experimental and theoretical in field of Tissue science, Health science, Regenerative medicine, Engineering and use of devices and biomaterial for disease diagnosis in biological system....View More
Journal of Medical Sciences and Health Care Research
Journal primary objective is to provide research and applications related to Medical & Health Sciences. This journal strives to serve a diverse readership by publishing articles in a wide range of topics. This journal will welcome articles from the field of all specialities medical science that includes feilds like medicine...View More
International Journal of Catalysis and Chemical Engineering
International Journal of Catalysis and Chemical Engineering (IJCCE) is a scholarly open access per-reviewed journal aim to publish be valuable source of information in field of Chemical Engineering, Catalysis, Catalytic Materials & Mechanisms, Nanocatalysis....View More