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Clonal Complex
Clonal may refer to: Biology *Clonal interference, a phenomenon that occurs when two (or more) beneficial mutations arise independently in different individuals in a genetically homogeneous population of an asexually reproducing organism *Aggregating anemone, also called clonal anemone *Vegetative cloning, a form of asexual reproduction in plants *Clonal reproduction Immunology *Clonal deletion, a process by which B cells and T cells are deactivated before act significantly upon specific antigens *Clonal selection theory, a model for how the immune system responds to infection *Clonal anergy, a lack of reaction by the body's defense mechanisms to foreign substance See also *Clone (other) *Clonalis House *Clone (genetics) *Cloning Cloning is the process of producing individual organisms with identical genomes, either by natural or artificial means. In nature, some organisms produce clones through asexual reproduction; this reproduction of an organism by itself with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clonal Interference
Clonal interference is a phenomenon in evolutionary biology, related to the population genetics of organisms with significant linkage disequilibrium, especially asexually reproducing organisms. The idea of clonal interference was introduced by American geneticist Hermann Joseph Muller in 1932. It explains why beneficial mutations can take a long time to get fixated or even disappear in asexually reproducing populations. As the name suggests, clonal interference occurs in an asexual lineage ("clone") with a beneficial mutation. This mutation would be likely to get fixed if it occurred alone, but it may fail to be fixed, or even be lost, if another beneficial-mutation lineage arises in the same population; the multiple clones interfere with each other. Mechanism of clonal interference Whenever a beneficial mutation arises in a population, for example mutation A, the carrier of the mutation obtains a higher fitness compared to members of the population without mutation A by means ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aggregating Anemone
The aggregating anemone (''Anthopleura elegantissima''), or clonal anemone, is the most abundant species of sea anemone found on rocky, tide swept shores along the Pacific coast of North America. This cnidarian hosts endosymbiotic algae called zooxanthellae that contribute substantially to primary productivity in the intertidal zone. The aggregating anemone has become a model organism for the study of temperate cnidarian-algal symbioses. They are most well known for the ability to clone themselves. Description The polyps of the aggregating anemone reach up to eight cm across the oral disk with approximately 100 tentacles in three or four rows around the margins of the oral disk. Most are olive to bright green (depending on the species of algal symbionts present) with tentacles tipped in pink. Individuals that live in microhabitats that are deficient in photosynthetically active radiation (PAR), such as under docks or in caves, lack symbionts and are pale yellow to white in colo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vegetative Cloning
Vegetative reproduction (also known as vegetative propagation, vegetative multiplication or cloning) is a form of asexual reproduction occurring in plants in which a new plant grows from a fragment or cutting of the parent plant or specialized reproductive structures, which are sometimes called vegetative propagules. Many plants naturally reproduce this way, but it can also be induced artificially. Horticulturists have developed asexual propagation techniques that use vegetative propagules to replicate plants. Success rates and difficulty of propagation vary greatly. Monocotyledons typically lack a vascular cambium, making them more challenging to propagate. Plant propagation Plant propagation is the process of plant reproduction of a species or cultivar, and it can be sexual or asexual. It can happen through the use of vegetative parts of the plants, such as leaves, stems, and roots to produce new plants or through growth from specialized vegetative plant parts. While m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clonal Reproduction
Cloning is the process of producing individual organisms with identical genomes, either by natural or artificial means. In nature, some organisms produce clones through asexual reproduction; this reproduction of an organism by itself without a mate is known as parthenogenesis. In the field of biotechnology, cloning is the process of creating cloned organisms of cells and of DNA fragments. The artificial cloning of organisms, sometimes known as reproductive cloning, is often accomplished via somatic-cell nuclear transfer (SCNT), a cloning method in which a viable embryo is created from a somatic cell and an egg cell. In 1996, Dolly the sheep achieved notoriety for being the first mammal cloned from a somatic cell. Another example of artificial cloning is molecular cloning, a technique in molecular biology in which a single living cell is used to clone a large population of cells that contain identical DNA molecules. In bioethics, there are a variety of ethical positions regar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clonal Deletion
In immunology, clonal deletion is the process of removing T and B lymphocytes from the immune system repertoire. The process of clonal deletion helps prevent recognition and destruction of the self host cells, making it a type of Negative selection (immunology), negative selection. Ultimately, clonal deletion plays a role in central tolerance.Jenni., Punt; A., Stranford, Sharon; P., Jones, Patricia; Janis., Kuby (2013-01-01). ''Kuby immunology''. W.H. Freeman. Clonal deletion can help protect individuals against autoimmunity, which is when an organism produces and immune response on its own cells. It is one of many methods used by the body in immune tolerance. Discovery Central tolerance and clonal deletion did not get much attention in the early years of immunology. Macfarlane Burnet, Frank Macfarlane Burnet was the first to suggest the idea of clonal deletion. A couple key findings helped Burnet's in this discovery. In 1936, Erich Traub demonstrated that when a developing m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clonal Selection
In immunology, clonal selection theory explains the functions of cells of the immune system (lymphocytes) in response to specific antigens invading the body. The concept was introduced by Australian doctor Frank Macfarlane Burnet in 1957, in an attempt to explain the great diversity of antibodies formed during initiation of the immune response. The theory has become the widely accepted model for how the human immune system responds to infection and how certain types of B and T lymphocytes are selected for destruction of specific antigens. The theory states that in a pre-existing group of lymphocytes (both B and T cells), a specific antigen activates (i.e. selects) only its counter-specific cell, which then induces that particular cell to multiply, producing identical clones for antibody production. This activation occurs in secondary lymphoid organs such as the spleen and the lymph nodes. In short, the theory is an explanation of the mechanism for the generation of diversity ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anergy
In immunology, anergy characterizes the absence of a response from the body's defense mechanisms when confronted with foreign substances. This phenomenon involves the direct induction of peripheral lymphocyte tolerance. When an individual is in a state of anergy, it signifies that their immune system is incapable of mounting a typical response against a specific antigen, typically a self-antigen. The term anergy specifically refers to lymphocytes that exhibit an inability to react to their designated antigen. Notably, anergy constitutes one of the essential processes fostering tolerance within the immune system, alongside clonal deletion and immunoregulation. These processes collectively act to modify the immune response, preventing the inadvertent self-destruction that could result from an overactive immune system. Mechanism This phenomenon was first described in B lymphocytes by Gustav Nossal and termed "clonal anergy." The clones of B lymphocytes in this case can still b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clone (other)
Clone or Clones or Cloning or Cloned or The Clone may refer to: Places * Clones, County Fermanagh, Ireland * Clones, County Monaghan, a town in Ireland * Clones railway station, Ireland Biology * Clone (B-cell), a lymphocyte clone, the massive presence of which may indicate a pathological condition * Clone (cell biology), a group of identical cells that share a common ancestry * Clonal plant, the result of asexual, vegetative reproduction when a new plant grows from a fragment of the parent plant * Cloning, the production of any organism whose genetic information is identical to that of a parent organism from which it was created Computing and technology * Clone (computing), computer hardware or software designed to function in the same way as an original ** Video game clone, a software game or game franchise heavily inspired by another ** ''Clones'' (video game), a video game clone ''Lemmings'' * Clone (Java method), a method in the Java programming language for object dupli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clonalis House
Clonalis House () is an historic manor house in Castlerea, County Roscommon, Ireland, and the ancestral home of the O'Conor Don, who are direct descendants of Cathal Crobhdearg Ua Conchobair, King of Connacht, a younger brother of Ruaidrí Ua Conchobair, the last High King of Ireland. The current building was constructed in 1878 by Charles Owen O'Conor as a replacement for an earlier house on the same site which was frequently damaged by flooding. Built of mass concrete, its design by Frederick Pepys Cockerell is of a mixture of styles drawing on the traditions of Italianate and Queen Anne Style architecture. Its history reflects the turbulence of Irish history, having once been occupied by the Irish Republican Army before it was shelled and captured by Free State Forces during the Irish Civil War The Irish Civil War (; 28 June 1922 – 24 May 1923) was a conflict that followed the Irish War of Independence and accompanied the establishment of the Irish Free State, an e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clone (genetics)
Molecular cloning is a set of experimental methods in molecular biology that are used to assemble recombinant DNA molecules and to direct their replication within host organisms. The use of the word ''cloning'' refers to the fact that the method involves the replication of one molecule to produce a population of cells with identical DNA molecules. Molecular cloning generally uses DNA sequences from two different organisms: the species that is the source of the DNA to be cloned, and the species that will serve as the living host for replication of the recombinant DNA. Molecular cloning methods are central to many contemporary areas of modern biology and medicine. In a conventional molecular cloning experiment, the DNA to be cloned is obtained from an organism of interest, then treated with enzymes in the test tube to generate smaller DNA fragments. Subsequently, these fragments are then combined with vector DNA to generate recombinant DNA molecules. The recombinant DNA is then ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
