Essay On Continuity Of Life

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The continuity of life is based on heritable information in the form of DNA and is transferred from one generation to another.
According to ‘The Free Dictionary by Farlex’ the definition of heredity is: “1. (Biology) the transmission from one generation to another of genetic factors that determine individual characteristics: responsible for the resemblances between parents and offspring.” The continuity of life is based on this fact and will be discussed in this essay.
This is tied very close to genetics an area of biological study interested in hereditary traits. For many years people had a common understanding about genetic inheritance and that it consists of certain traits that are passed along one generation to the next, but it was mostly subjective and due to casual observation and not scientific study. Then in 1866 the Austrian monk Gregor Mendel entered the scene.
In his short monograph ‘Experiments with Plant Hybrids’ he published the results of his study in which he crossed pea plants of the same species that differed in only one trait. The result of his studies was a few basic laws of heredity: “hereditary factors do not combine, but are passed intact; each member of the parental generation transmits only half of its hereditary factors to each offspring (with certain factors "dominant" over others); and different offspring of the same parents receive different sets of hereditary factors.” (Access excellence @ the National Health Museum 1999-2009)
But although this was some ground-breaking discoveries his ideas was over looked and he died in anonymity. In 1900 another geneticist Hugo de Vries published another paper where he also proved Mendel’s work but he brought in the theory of mutations- genetic changes happen in ...

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...e chromosome pairs in diploid organisms separate into individual haploid gametes- sperm and eggs- to transfer the genetic information to the offspring.
His concept of dominance explains how one gets dominant and recessive alleles and the effect of this. Dominant alleles completely hide the properties of recessive alleles and produce the same phenotype whether it is heterozygotes or homozygotes. Recessive alleles properties only show if it is homozygous.
His concept of independent assortment explains how alleles on different chromosomes are distributed randomly to individual gametes (http://www.dummies.com/how-to/content/mendels-laws-of-inheritance.html). This combined with his law of segregation ensures genetic variation.
Another factor we consider is his rules of probability which can be used to examine passage of an individual gene traits from parent to offspring.

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