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Design Media Arts at UCLA
Peter Ng (M)
South Pasadena, US
Immortal since Mar 29, 2007
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    From petergng
    Final Visuals + Sounds
    petergng’s project
    Design Media Arts at UCLA
    In the 1970s space colonies were considered to be a viable alternative to a life restricted to planet Earth. The design of cylindrical space...
    Now playing SpaceCollective
    Where forward thinking terrestrials share ideas and information about the state of the species, their planet and the universe, living the lives of science fiction. Introduction
    Featuring Powers of Ten by Charles and Ray Eames, based on an idea by Kees Boeke.
    From petergng's personal cargo

    Heredity
    Project: Design Media Arts at UCLA

    Gregor Mendel's work provided the first firm basis for the idea that heredity occurred in discrete units. He noticed several traits in peas that occur in only one of two forms (e.g., the peas were either "round" or "wrinkled"), and was able to show that the traits were: heritable (passed from parent to offspring); discrete (i.e., if one parent had round peas and the other wrinkled, the progeny were not intermediate, but either round or wrinkled); and distributed to progeny in a well-defined and predictable manner (Mendelian inheritance). His research laid the foundation for the concept of discrete heritable traits, known today as genes.

    The concepts involved in Mendel's experiments have been found to have wide applicability, and most complex traits have been found to be polygenetic and not controlled by single-unit characters. Mendel's ideas replaced the notion of "blending inheritance" prevalent at the time Darwin wrote The Origin of Species, and answered the long-standing problem of the persistence of variation within populations.

    Later research gave a physical basis to the notion of genes, and eventually identified DNA as the heritable material, with genes re-defined and functioning as discrete regions within DNA. DNA is not perfectly copied, and rare mistakes (mutations) in genes can affect traits that the genes control (e.g., pea shape).

    A gene can have modifications such as DNA methylation, which do not change the nucleotide sequence of a gene, but do result in the epigenetic inheritance of a change in the expression of that gene in a trait. Another epigenetic mechanism is via microRNA and RNA interference, which serve regulatory roles in gene transcription and translation.

    Non-DNA based forms of heritable variation exist, such as transmission of the secondary structures of prions or structural inheritance of patterns in the rows of cilia in protozoans such as Paramecium[13] and Tetrahymena.[14] Investigations continue into whether these mechanisms allow for the production of specific beneficial heritable variation in response to environmental signals. If this were shown to be the case, then some instances of evolution would lie outside of the typical Mendelian framework, which avoids any connection between environmental signals and the production of heritable variation. However, the processes that produce these variations are rather rare, often reversible, and leave the genetic information intact.

    Mon, Apr 16, 2007  Permanent link

    Sent to project: Design Media Arts at UCLA
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