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Cepaea Nemoralis Unten
''Cepaea'' is a genus of large air-breathing land snails, terrestrial pulmonate gastropod molluscs in the family Helicidae. The shells are often brightly coloured and patterned with brown stripes. The two living species in this genus, ''C. nemoralis'' and ''C. hortensis'', are widespread and common in Western and Central Europe. In North America, ''C. hortensis'' is native on the northeast coast, but both species have been introduced elsewhere, and they are also spreading further east in Europe. Both have been influential model species for ongoing studies of genetics and natural selection. Like many Helicidae, these snails use love darts during mating. Species For a long time, four living species were classified in the genus ''Cepaea''. However, molecular phylogenetic studies suggested that two of them should be placed in the genera '' Macularia'' and '' Caucasotachea'', which are not immediate relatives of either ''Cepaea'' or each other: * '' Cepaea hortensis'' (O. F. Müll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedum Cepaea
''Sedum cepaea'', the pink stonecrop, is a species of flowering plant in the family Crassulaceae. It has a Mediterranean distribution, but generally in the mountains, and extending into France as far north as Paris, and it has been introduced to Belgium, Germany, and, it seems, New Zealand. A bushy, succulent annual, it can reach . References cepaea ''Cepaea'' is a genus of large air-breathing land snails, terrestrial molluscs, terrestrial pulmonate gastropod molluscs in the family Helicidae. The shells are often brightly coloured and patterned with brown stripes. The two living species in ... Flora of Switzerland Flora of Southwestern Europe Flora of Southeastern Europe Flora of the East Aegean Islands Flora of Turkey Flora of Syria Flora of North Africa Taxa named by Carl Linnaeus Plants described in 1753 {{Crassulaceae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cepaea Nemoralis
The grove snail, brown-lipped snail or lemon snail (''Cepaea nemoralis'') is a species of air-breathing land snail, a terrestrial molluscs, terrestrial pulmonate gastropod mollusc. It is one of the most common large species of land snail in Europe, and has been introduced to North America. ;Subspecies: * ''Cepaea nemoralis etrusca'' (Rossmässler, 1835) * ''Cepaea nemoralis nemoralis'' (Linnaeus, 1758) ''Cepaea nemoralis'' is the type species of the genus ''Cepaea''. It is used as a model organism in ecological genetics, including in citizen science projects. Description ''Cepaea nemoralis'' is among the largest and, because of its bright colouration, one of the best-known snails in Western Europe. The colour of the gastropod shell, shell is highly variable; it ranges from brown, through pink, to yellow or even whitish, with or without one to five dark-brown bands. Names for many colour variants were coined in the nineteenth century but this system has been replaced by an inde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proportion Yellow Cepaea Nemoralis Silvertown2011
Proportionality, proportion or proportional may refer to: Mathematics * Proportionality (mathematics), the property of two variables being in a multiplicative relation to a constant * Ratio, of one quantity to another, especially of a part compared to a whole ** Fraction (mathematics) * Aspect ratio or proportions * Proportional division, a kind of fair division * Percentage, a number or ratio expressed as a fraction of 100 Science and art * Proportional fonts * Proportionally fair, a scheduling algorithm * Proportional control, a type of linear feedback control system Other uses * Proportionality (law), a legal principle * Proportionality (International Humanitarian Law), a law of war * Proportion (architecture), describes the relationships between elements of a design * Body proportions, in art, the study of relation of human body parts to each other and the whole See also * Proportional representation Proportional representation (PR) refers to any electoral system under wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Linkage Disequilibrium
Linkage disequilibrium, often abbreviated to LD, is a term in population genetics referring to the association of genes, usually linked genes, in a population. It has become an important tool in medical genetics and other fields In defining LD, it is important first to distinguish the two very different concepts, linkage disequilibrium and linkage (genetic linkage). Linkage disequilibrium refers to the association of genes ''in a population.'' Linkage, on the other hand, tells us whether genes are on the same chromosome ''in an individual''. There is no necessary relationship between the two. Genes that are closely linked may or may not be associated in populations. Looking at parents and offspring, if genes at closely linked loci are together in the parent then they will usually be together in the offspring. But looking at individuals in a population with no known common ancestry, it is much more difficult to see any relationships. To give a concrete, although imaginary, example i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supergene
A supergene is a chromosomal region encompassing multiple neighboring genes that are inherited together because of close genetic linkage, i.e. much less recombination than would normally be expected. This mode of inheritance can be due to genomic rearrangements between supergene variants. A supergene region can contain few, functionally related genes that clearly contribute to a shared phenotype. Phenotypes encoded by supergenes Supergenes have cis-effects due to multiple loci (which may be within a gene, or within a single gene's regulatory region), and tight linkage. They are classically polymorphic, whereby different supergene variants code for different phenotypes. Classic supergenes include many sex chromosomes, the ''Primula'' heterostyly locus, which controls " pin" and " thrum" types, and the locus controlling Batesian mimetic polymorphism in '' Papilio memnon'' butterflies. Recently discovered supergenes are responsible for complex phenotypes including color-m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Linkage
Genetic linkage is the tendency of Nucleic acid sequence, DNA sequences that are close together on a chromosome to be inherited together during the meiosis phase of sexual reproduction. Two Genetic marker, genetic markers that are physically near to each other are unlikely to be separated onto different Chromatid, chromatids during chromosomal crossover, and are therefore said to be more ''linked'' than markers that are far apart. In other words, the nearer two Gene, genes are on a chromosome, the lower the chance of Genetic recombination, recombination between them, and the more likely they are to be inherited together. Markers on different chromosomes are perfectly ''unlinked'', although the penetrance of potentially deleterious alleles may be influenced by the presence of other alleles, and these other alleles may be located on other chromosomes than that on which a particular potentially deleterious allele is located. Genetic linkage is the most prominent exception to Gregor M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dominance (genetics)
In genetics, dominance is the phenomenon of one variant (allele) of a gene on a chromosome masking or overriding the effect of a different variant of the same gene on the other copy of the chromosome. The first variant is termed dominant and the second is called recessive. This state of having two different variants of the same gene on each chromosome is originally caused by a mutation in one of the genes, either new (''de novo'') or inherited. The terms autosomal dominant or autosomal recessive are used to describe gene variants on non-sex chromosomes ( autosomes) and their associated traits, while those on sex chromosomes (allosomes) are termed X-linked dominant, X-linked recessive or Y-linked; these have an inheritance and presentation pattern that depends on the sex of both the parent and the child (see Sex linkage). Since there is only one Y chromosome, Y-linked traits cannot be dominant or recessive. Additionally, there are other forms of dominance, such as incomp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Locus (genetics)
In genetics, a locus (: loci) is a specific, fixed position on a chromosome where a particular gene or genetic marker is located. Each chromosome carries many genes, with each gene occupying a different position or locus; in humans, the total number of Human genome#Coding sequences (protein-coding genes), protein-coding genes in a complete haploid set of 23 chromosomes is estimated at 19,000–20,000. Genes may possess multiple variants known as alleles, and an allele may also be said to reside at a particular locus. Diploid and polyploid cells whose chromosomes have the same allele at a given locus are called homozygote, homozygous with respect to that locus, while those that have different alleles at a given locus are called heterozygote, heterozygous. The ordered list of loci known for a particular genome is called a gene map. Gene mapping is the process of determining the specific locus or loci responsible for producing a particular phenotype or biological trait. Association ma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alleles
An allele is a variant of the sequence of nucleotides at a particular location, or locus, on a DNA molecule. Alleles can differ at a single position through single nucleotide polymorphisms (SNP), but they can also have insertions and deletions of up to several thousand base pairs. Most alleles observed result in little or no change in the function or amount of the gene product(s) they code or regulate for. However, sometimes different alleles can result in different observable phenotypic traits, such as different pigmentation. A notable example of this is Gregor Mendel's discovery that the white and purple flower colors in pea plants were the result of a single gene with two alleles. Nearly all multicellular organisms have two sets of chromosomes at some point in their biological life cycle; that is, they are diploid. For a given locus, if the two chromosomes contain the same allele, they, and the organism, are homozygous with respect to that allele. If the alleles are differ ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grove Snail Cepaea Nemoralis, Showing Colour And Banding Polymorphism
Grove may refer to: * Grove (nature), a small group of trees Places England * Grove, Buckinghamshire, a village *Grove (ward), an electoral ward of Hammersmith and Fulham London Borough Council that existed from 1964 to 2002, and then was reformed in 2022 * Grove, Nottinghamshire, a village *Grove, Oxfordshire, a village and civil parish * Hazel Grove, Stockport, a suburb * The Grove, County Durham, a village * The Grove, Dorset United States * Grove, Maine * Grove, New York, a town * Grove, Oklahoma, a city * Grove, Virginia, an unincorporated community * Grove, West Virginia * Grove Township (other), various townships Elsewhere * Grove, Tasmania, Australia, a suburb * Grove, Germany, a municipality in Schleswig-Holstein * Grove, County Leitrim, a townland in Ireland * O Grove, Galicia, Spain, a municipality * Grove (crater), on the Moon Schools * Grove Primary School (other) *Grove Academy Other uses *Grove (surname) *, a Second World War destroye ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Backcross
Backcrossing is a crossing of a hybrid with one of its parents or an individual genetically similar to its parent, to achieve offspring with a genetic identity closer to that of the parent. It is used in horticulture, animal breeding, and production of gene knockout organisms. Backcrossed hybrids are sometimes described with acronym "BC"; for example, an F1 hybrid crossed with one of its parents (or a genetically similar individual) can be termed a BC1 hybrid, and a further cross of the BC1 hybrid to the same parent (or a genetically similar individual) produces a BC2 hybrid. Plants Advantages * If the recurrent parent is an elite genotype, at the end of the backcrossing programme, an elite genotype is recovered. * As no "new" recombination results, the elite combination is not lost. Disadvantages * It works poorly for quantitative traits. * It is more restricted for recessive traits. * In practice, sections of genome from the nonrecurrent parents are often still present and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
