0
300-500 = -200
Georgianna Rohan
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How much bigger is as 235 75 15 tire than a 205 70 15?
300500
Is the distance from Denver Colorado to Santa Fe New Mexico 300500 or 800 miles?
Neither. Depending on your route, you're looking at 350 to 390 miles - the 390 mile route is actually a faster route than the 350 mile route.
Who does Albinism commonly affect?
http://en.wikipedia.org/wiki/Albinism Albino" redirects here. For other uses, see Albino (disambiguation). Semi-protected Albinism Classification and external resources Girl from Honduras with probable OCA1a-type albinism. ICD-10 E70.3 ICD-9 270.2 OMIM 203100 103470, 203200, 203280, 203290, 203300, 203310, 256710, 278400, 214450, 214500, 220900, 300500, 300600, 300650, 300700, 600501, 604228, 606574, 606952, 607624, 609227 DiseasesDB 318 MedlinePlus 001479 eMedicine derm/12 MeSH D000417 Albinism (from Latin albus, "white"; see extended etymology, also called achromia, achromasia, or achromatosis; not to be confused with albedo) is a form of hypopigmentary congenital disorder, characterized by a partial (in hypomelanism, also known as hypomelanosis) or total (amelanism or amelanosis) lack of melanin pigment in the eyes, skin and hair (or more rarely the eyes alone). Albinism results from inheritance of recessive alleles. The condition is known to affect mammals (including humans), fish, birds, reptiles and amphibians. While the most common term for an organism affected by albinism is "albino" (noun and adjective), the word is sometimes used in derogatory ways towards people; more neutral terms are "albinistic" (adjective) and "person with albinism" (noun). Additional clinical adjectives sometimes used to refer to animals are "albinoid" and "albinic". Albinism is hereditary; it is not an infectious disease and cannot be transmitted through contact, blood transfusions, or other vectors. The principal gene which results in albinism prevents the body from making the usual amounts of the pigment melanin. Most forms of albinism are the result of the biological inheritance of genetically recessive alleles (genes) passed from both parents of an individual, though some rare forms are inherited from only one parent. There are other genetic mutations which are proven to be associated with albinism. All alterations, however, lead to changes in melanin production in the body.[1][2] Albinism was formerly categorized as tyrosinase-positive or -negative. In cases of tyrosinase-positive albinism, the enzyme tyrosinase is present. The melanocytes (pigment cells) are unable to produce melanin for any one of a variety of reasons that do not directly involve the tyrosinase enzyme. In tyrosinase-negative cases, either the tyrosinase enzyme is not produced or a nonfunctional version is produced. This classification has been rendered obsolete by recent research.[3] The chance of offspring with albinism resulting from the pairing of an organism with albinism and one without albinism is low, as discussed in more detail below. However, because organisms can be carriers of genes for albinism without exhibiting any traits, albinistic offspring can be produced by two non-albinistic parents. Albinism usually occurs with equal frequency in both genders.[1] An exception to this is ocular albinism, because it is passed on to offspring through X-linked inheritance. Thus, males more frequently have ocular albinism as they do not have a second X chromosome.[3] Albino Bennett's Wallaby, Bruny Island, Tasmania, Australia Because organisms with albinism have skin that lacks (sufficiently or entirely) the dark pigment melanin, which helps protect the skin from ultraviolet radiation coming from the sun, they can sunburn easily from overexposure. (See human skin color for more information). Lack of melanin in the eye also results in problems with vision, related and unrelated to photosensitivity, which are discussed further below. Most humans and many animals with albinism appear white or very pale; the multiple types of melanin pigment are responsible for brown, black, gray, and some yellow colorations. In some animals, especially albinistic birds and reptiles, ruddy and yellow hues or other colors may be present on the entire body or in patches (as is common among pigeons), due to the presence of other pigments unaffected by albinism such as porphyrins, pteridines and psittacins, as well as carotenoid pigments derived from the diet. Some animals are white or pale due to chromatophore (pigment cell) defects, do not lack melanin production, and have normal eyes; they are referred to as leucistic. The direct opposite of albinism, an unusually high level of melanin pigmentation (and sometimes absence of other types of pigment in species that have more than one), is known as melanism, and results in an appearance darker than non-melanistic specimens from the same genepool.[4] Albinism-like conditions may affect other pigments or pigment-production mechanisms in some animals (e.g. "whiteface", a lack of psittacins that can affect some parrot species.).[5] Another is common in reptiles and amphibians: axanthism, in which xanthophore metabolism, instead of synthesis of melanin, is affected, resuling in reduction or absence of red and yellow pteridine pigments.[6] Of all these conditions, only albinism and melanism affect humans. An albino Wistar rat, a strain commonly used for both biomedical and basic research. The eyes of an animal with albinism occasionally appear red due to the underlying retinal blood vessels showing through where there is not enough pigment to cover them. In humans this is rarely the case, as a human eye is quite large and thus produces enough pigment to lend opacity to the eye, often colouring the iris pale blue. However, there are cases in which the eyes of an albinistic person appear red or purple, depending on the amount of pigment present. The albinistic are generally (but see related disorders below) as healthy as the rest of their species, with growth and development occurring as normal, and albinism by itself does not cause mortality[1] (though the lack of pigment is an elevated risk for skin cancer and other problems.) Many animals with albinism lack their protective camouflage and are unable to conceal themselves from their predators or prey; the survival rate of animals with albinism in the wild is usually quite low.[7][8] However the novelty of albino animals has occasionally led to their protection by groups such as the Albino Squirrel Preservation Society. Intentionally-bred albinistic strains of some animal species are commonly used as model organisms in biomedical study and experimentation. Examples include the BALB/c mouse and Wistar and Sprague Dawley rat strains, while albino rabbits were historically used for Draize toxicity testing. [9] Albino axolotls, zebrafish, medaka and frogs are other common laboratory animals. The yellow mutation in fruit flies is their version of albinism. The incidence of albinism can be artificially increased in fish by exposing the eggs to heavy metals.[10] About 1 in 17,000 human beings has some type of albinism, although up to 1 in 70 is a carrier of albinism genes.[11]
