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Major Histocompatibility Complex And Sexual Selection
The major histocompatibility complex in sexual selection concerns how major histocompatibility complex (MHC) molecules allow for immune system surveillance of the population of protein molecules in a host's cells. In 1976, Yamazaki et al. demonstrated a sexual selection mate choice by male mice for females of a . Major histocompatibility complex genes, which control the immune response and effective resistance against pathogens, have been able to maintain an extremely high level of allelic diversity throughout time and throughout different populations. Studies suggest that the MHC is involved in mate choice for many vertebrates through olfactory cues. There are several proposed hypotheses that address how MHC-associated mating preferences could be adaptive and how an unusually large amount of allelic diversity has been maintained in the MHC. The vast source of genetic variation affecting an organism's fitness stems from the co-evolutionary arms race between hosts and parasites. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black-Throated Blue Warbler
The black-throated blue warbler (''Setophaga caerulescens'') is a small passerine bird of the New World warbler family. Its breeding ranges are located in the interior of deciduous and mixed coniferous forests in eastern North America. Over the cooler months, it migrates to islands in the Caribbean and Central America. It is very rarely found in western Europe, where it is considered to be a non-indigenous species. The black-throated blue warbler is sexually dimorphic; the adult male has a black face and cheeks, deep blue upperparts and white underparts, while the adult female is olive-brown above and light yellow below. Predominantly insectivorous, the black-throated blue warbler supplements its diet with berries and seeds in winter. It builds its nests in thick shrubs and the closeness of its nesting sites to the ground make it a favored species for the study of warbler behavior in the wild. The black-throated blue warbler defends its territory against other birds of the same ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mitosis, or meiosis or other types of damage to DNA (such as pyrimidine dimers caused by exposure to ultraviolet radiation), which then may undergo error-prone repair (especially microhomology-mediated end joining), cause an error during other forms of repair, or cause an error during replication (translesion synthesis). Mutations may also result from insertion or deletion of segments of DNA due to mobile genetic elements. Mutations may or may not produce detectable changes in the observable characteristics (phenotype) of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity. Mutation is the ultimate source o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PLoS Genet
''PLOS Genetics'' is a peer-reviewed open access scientific journal established in 2005 and published by the Public Library of Science. The founding editor-in-chief was Wayne N. Frankel (Columbia University Medical Center). The current editors-in-chief are Gregory S. Barsh ( HudsonAlpha Institute of Biotechnology and Stanford University School of Medicine) and Gregory P. Copenhaver (The University of North Carolina at Chapel Hill). The journal covers research on all aspects of genetics and genomics. Abstracting and indexing The journal is abstracted and indexed in: According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as ... of 5.917. Research Prize Since its tenth year of publication, the journal annuall ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hutterite
Hutterites (german: link=no, Hutterer), also called Hutterian Brethren (German: ), are a communal ethnoreligious group, ethnoreligious branch of Anabaptism, Anabaptists, who, like the Amish and Mennonites, trace their roots to the Radical Reformation of the early 16th century and have formed intentional communities. The founder of the Hutterites, Jacob Hutter, "established the Hutterite colonies on the basis of the Schleitheim Confession, a classic Anabaptist statement of faith" of 1527, and the first communes were formed in 1528. Since the death of Hutter in 1536, the beliefs of the Hutterites, especially those espousing a community of goods and nonresistance, have resulted in hundreds of years of diaspora in many countries. The Hutterites embarked on a series of migrations through central and eastern Europe. Nearly extinct by the 18th century, they migrated to Russian Empire, Russia in 1770 and about a hundred years later to North America. Over the course of 140 years, their p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J R Soc Med
The ''Journal of the Royal Society of Medicine'' is a peer-reviewed medical journal. It is the flagship journal of the Royal Society of Medicine with full editorial independence. Its continuous publication history dates back to 1809. Since July 2005 the editor-in-chief is Kamran Abbasi, who succeeded Robin Fox who was editor for almost 10 years. History The journal was established in 1806 as the ''Medico-Chirurgical Transactions'' published by the Royal Medical and Chirurgical Society of London. It was renamed to ''Proceedings of the Royal Society of Medicine'' in 1907, following the merger that led to the formation of the Royal Society of Medicine and with volume numbering restarting at 1, before obtaining its current name in 1978. Abstracting and indexing The journal is abstracted and indexed in MEDLINE/PubMed, Science Citation Index, EMBASE, CAB International, and Elsevier Biobase. According to the ''Journal Citation Reports'', the journal has a 2021 impact factor of 18.00 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vomeronasal Organ
The vomeronasal organ (VNO), or Jacobson's organ, is the paired auxiliary olfactory (smell) sense organ located in the soft tissue of the nasal septum, in the nasal cavity just above the roof of the mouth (the hard palate) in various tetrapods. The name is derived from the fact that it lies adjacent to the unpaired vomer bone (from Latin 'plowshare', for its shape) in the nasal septum. It is present and functional in all snakes and lizards, and in many mammals, including cats, dogs, cattle, pigs, and some primates. Some humans may have physical remnants of a VNO, but it is vestigial and non-functional. The VNO contains the cell bodies of sensory neurons which have receptors that detect specific non-volatile (liquid) organic compounds which are conveyed to them from the environment. These compounds emanate from prey, predators, and the compounds called sex pheromones from potential mates. Activation of the VNO triggers an appropriate behavioral response to the presence of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pheromone
A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavior of the receiving individuals. There are ''alarm signal, alarm pheromones'', ''food trail pheromones'', ''sex pheromones'', and many others that affect behavior or physiology. Pheromones are used by many organisms, from basic unicellular prokaryotes to complex multicellular eukaryotes. Their use among insects has been particularly well documented. In addition, some vertebrates, plants and ciliates communicate by using pheromones. The ecological functions and evolution of pheromones are a major topic of research in the field of chemical ecology. Background The portmanteau word "pheromone" was coined by Peter Karlson and Martin Lüscher in 1959, based on the Greek φερω ''pheroo'' ('I carry') and ὁρμων ''hormon'' ('stimulating'). P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olfactory System
The olfactory system, or sense of smell, is the sensory system used for smelling (olfaction). Olfaction is one of the special senses, that have directly associated specific organs. Most mammals and reptiles have a main olfactory system and an accessory olfactory system. The main olfactory system detects airborne substances, while the accessory system senses fluid-phase stimuli. The senses of smell and taste (gustatory system) are often referred to together as the chemosensory system, because they both give the brain information about the chemical composition of objects through a process called transduction. Structure Peripheral The peripheral olfactory system consists mainly of the nostrils, ethmoid bone, nasal cavity, and the olfactory epithelium (layers of thin tissue covered in mucus that line the nasal cavity). The primary components of the layers of epithelial tissue are the mucous membranes, olfactory glands, olfactory neurons, and nerve fibers of the olfactory nerves. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proc
Proc may refer to: * Proč, a village in eastern Slovakia * '' Proč?'', a 1987 Czech film * procfs or proc filesystem, a special file system (typically mounted to ) in Unix-like operating systems for accessing process information * Protein C (PROC) * Proc, a term in video game terminology * Procedures or process, in the programming language ALGOL 68 * People's Republic of China, the formal name of China China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and ... * the official acronym for the Canadian House of Commons Standing Committee on Procedure and House Affairs {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Diversity
Genetic diversity is the total number of genetic characteristics in the genetic makeup of a species, it ranges widely from the number of species to differences within species and can be attributed to the span of survival for a species. It is distinguished from ''genetic variability'', which describes the tendency of genetic characteristics to vary. Genetic diversity serves as a way for populations to adapt to changing environments. With more variation, it is more likely that some individuals in a population will possess variations of alleles that are suited for the environment. Those individuals are more likely to survive to produce offspring bearing that allele. The population will continue for more generations because of the success of these individuals. The academic field of population genetics includes several hypotheses and theories regarding genetic diversity. The neutral theory of evolution proposes that diversity is the result of the accumulation of neutral substitutions ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Polymorphism
A gene is said to be polymorphic if more than one allele occupies that gene's locus within a population. In addition to having more than one allele at a specific locus, each allele must also occur in the population at a rate of at least 1% to generally be considered polymorphic. Gene polymorphisms can occur in any region of the genome. The majority of polymorphisms are silent, meaning they do not alter the function or expression of a gene. Some polymorphisms are visible. For example, in dogs the E locus can have any of five different alleles, known as E, Em, Eg, Eh, and e. Varying combinations of these alleles contribute to the pigmentation and patterns seen in dog coats. A polymorphic variant of a gene can lead to the abnormal expression or to the production of an abnormal form of the protein; this abnormality may cause or be associated with disease. For example, a polymorphic variant of the gene encoding the enzyme CYP4A11, in which thymidine replaces cytosine at the gene's nu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
