Clonal

... Oldest tree http://en.wikipedia.org/wiki/Methuselah_%28tree%29 Its age of around 4844–4845 years[a] makes it the world's oldest known living non-clonal organism. The ancient tree is named after Methuselah, a Biblical figure having the longest mentioned lifespan in the Bible of 969 years. Scientific ...

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... to environments without (random) mutation? It is quite easy to design experiments that falsify this. For example - take a cell, form several clonal populations from it - so the populations are identical except for random changes. Expose them to stress, enough to slow their growth but not ...

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... one gene (or group of very strongly linked genes) is involved. The conclusion are that what causes the spread of the melanic phenotype was due to clonal expansion of a single carbonaria ancestor (if the events had happened multiple times, one would expect diversity within the SNPs in the studied ...

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... the properties of T cells responding to the T cell receptor signals. Although the article focused mainly on autoimmunity, they said that many clonal TCRs can recognize several epitopes with varying affinities - with varying outcomes. So even if a virus could invade the thymus and thus eliminate ...

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... cells, to the contrary, do not require APCs and they do not adapt according to the type of antigen or infection (unlike T and B cells, who undergo clonal expansion and increased antibody affinity etc.). Thus, NK cells are considered to be a part of the innate immune system: they always recognize ...

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