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A phenotypic trait, or simply trait, is a distinct variant of a phenotypic characteristic of an organism that may be inherited, be environmentally determined or be a combination of the two.〔Lawrence, Eleanor (2005) ''Henderson's Dictionary of Biology''. Pearson, Prentice Hall. ISBN 0-13-127384-1〕 For example, eye color is a ''character'' or abstraction of an attribute, while blue, brown and hazel are ''traits''. == Definition == Phenotypic trait is the element the descriptions of individuals and groups of living creatures. Individualized biological variability (biodiversity) of each species and populations of living beings, includes all the components of individual features or individuality and group identity in morphological and anatomical, biochemical and ethological, and every other way, from the level of molecules to living communities and a higher degrees of ecological integration. Individuals and groups differ among themselves biologically, in practically endless succession of more or less visible elements of their descriptions, which are named as trait, feature, mark, nature, characteristics, character and others. Each of these components is a description of, say, the observational nature, i.e. selected part of our vision or measuring the actual condition of the individual body or group structure. When it comes to individual variability, leg, leaf or capsule, e.g., are not traits, but authorities where we see a lot of features such as: total length, aspect ratio and size of the parts, the degree of pigmentation and schedule, strength and a huge number of other elements of its description. Similarly, the human eye is organ aparatus, and some of its features are: size, shape, color of the iris, a variety of functional (dis)abilities and so on. Blood is a liquid tissue, characterized by: the total amount in the body, the number of erythrocytes, leukocytes and platelets per unit volume, the concentration of sugar and other substances, group specificity of erythrocytes (blood), hemoglobin concentration, and many others. While based on individual, group characteristics represent a new quality and a higher level of variability, and have different methods of observation and measurement. In simple, it can be concluded that the overall biology is based on the study of individual characteristics, from the molecular level to the full body and its relationship to the environment. The nature of the variation of individual properties in the observed group can be described according to various criteria. Primary observation of individual traits is that some of them with all the members of the group studied occur in a compatible form or ''variant'', the second - in two, and the rest in three or more mutually different varieties (''phenotypes'', ''variables'','' modalities'', ''forms''). On this basis, all the properties of the human body can be divided into ''monomorphic'' (red blood, for example.), ''dimorphic'' (Rh blood group system: ''Rh''+ and ''Rh''–) and ''polymorphic'' (series of variations of height, weight, surface, erytrocyte quantity in 1 ml of blod, and IQ, for example.); term and study the variability of the (course) refer only to the dimorphic and polymorphic features. According to the nature of intragroup variability (''the type of variations''), all features can be divided into two basic, very diverse categories: *''qualitative'', and *''quantitative'' traits. So, a phenotypic trait is an obvious and observable trait; it is the expression of genes in an observable way. An example of a phenotypic trait is hair color; there are underlying genes that control the hair color, which make up the genotype, but the actual hair color, the part we see, is the phenotype. The phenotype is the physical characteristics of the organism. The phenotype is controlled by the genetic make-up of the organism and the environmental pressures the organism is subject to.〔 *〕 A trait may be any single feature or quantifiable measurement of an organism. However, the most useful traits for genetic analysis are present in different forms in different individuals. A visible trait is the final product of many molecular and biochemical processes. In most cases, information starts with DNA traveling to RNA and finally to protein (ultimately affecting organism structure and function). This is the central dogma of molecular biology as stated by Francis Crick. This information flow may also be followed through the cell as it travels from the DNA in the nucleus, to the cytoplasm, to the ribosomes and the endoplasmic reticulum, and finally to the Golgi apparatus, which may package the final products for export outside the cell. Cell products are released into the tissue, and organs of an organism, to finally affect the physiology in a way that produces a trait. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「phenotypic trait」の詳細全文を読む スポンサード リンク
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