General Genetics/Mutations and Evolution

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Its often not grandiose, overlapping theories such as the Neutral Theory of Evolution, or Modern Synthesis, that biologists work with in their research on a day-to-day basis. Instead, it is the beautiful basics of genetics that are the cornerstone of experiments. The basics are then used to reflect on bigger ideas, such as population ecology and evolution. It is the beautiful basics of genetics with which we concern ourselves in this section.

Every organism has a set of genes and half of the genes of that organism come from each parent. The combinations of the genes causes the variation of individuals within the species. The genes of a butterfly, an ape or a fowl carry the code that determines the appearance and the character of the butterfly, the ape and the fowl. The genetic code allows an overwhelming variety within the species of the kind. A mutation is basically a gene that has an abnormality in relation to its normal configuration. The abnormality can then be passed to successive offspring, thereby producing a marked difference. There are many different types of mutations. The smallest possible genetic mutation is a 'point-mutation'. This occurs in the DNA when the base-pairs combine with the 'wrong' partner. Multiple point-mutations are common and are found to increase substantially by the effect of mutagens. Mutations are, of course, heritable and these can extend to whole or part chromosomal mutations. Because many genes are affected by a chromosomal mutation, these often have drastic ramifications on the offspring.