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Gregor Mendel and his work

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Introduction

GREGOR MENDEL 1822-1884 'The father of heredity' Gregor Mendel was an Austrian monk who taught natural science to high school students (see fig. 1). However, he also played a vital role in the history of genetics. His research and now famous experiments helped future scientists understand the laws of heredity. At the time, Mendel's work was unvalued by many scientists and it was rediscovered in the 20th century. In 1900, people saw a connection between meiosis and Mendel's work. This founder of heredity knew nothing of chromosomes, DNA or genes, but discovered patterns in his results which led to his powerful findings. His love of nature drew him in to researching the effects of the enviroment on plants, but instead he came along to identify how and why plants obtained irregular or regular characterists. Most of Mendels work was allocated to the garden pea, the Pisum, however he also did genetic work with other plants and honey bees. Figure 1: Image of Gregor Mendel Mendel was the first person to analyse and look into the charcterists of generations and thus came to be referred as the father of heredity. The famous pea expriment was the beginning of Mendels work and he started by growing a number of different variaties. ...read more.

Middle

The F2 generation always had offspring exposing both parental traits. Mendel described the frequent trait in F1 generation as dominant and if the trait overlept the F1 generation and be in in the F2 generation it was called recessive. The trait reappeared and disappered in the hybrid plants, and Mendel mathematically drew his conclusions about what was happening deep inside the cell. He found a ratio of 3:1 when he crossed monohybrid with monhybrid (Aa x Aa). Mendel then went onto cross plants which differed in more than one trait and again found a predictable ratio. This was 9:3:3:1 when he crossed dihybrid with dihybrid (AaBb x AaBb). This confirmed that traits were passed indivdually to the offspring and were not linked in any other way. The expriments showed both monohybrid inheritance and dihybrid inheritance. Monohybrid inheritance is the pattern of inheritance of a charcterist influenced by a single pair of alleles. Dihybrid inheritance is the study of the inheritance of two charcterists that are determined by genes on different non homolgous chromosomes. Mendel showed monohybrid crosses when he exprimented with just one characterist from the element, such as tallness and shortess of the stem, and self pollinated the two. ...read more.

Conclusion

In Mendels second law, he said either of the alleles in a pair (A or a) can combine with either of another pair (B or b). The modern version for this second law now stands as the law of independent assortment, which states that pairs of alleles separate independently of each other during the gamete formation. In 1866 Mendel published his work on heredity in the Journal of the Brno Natural History Society. It had absolutely no affect and his complex and detailed work was not understood by anyone of the time. The findings of Mendels expriments and his laws basically laid the foundations for the science of genetics. Along with Mendels findings and improved microscopes of the 20th century, chromosomes and DNA were discovered. Mendel did not live to see how much of an impact his work had on the world. This new science of heredity and variation was named 'genetics' by a British sciencist, and later Mendels 'elements' were known as genes. This essay not only reveals Mendels work into the theories of heredity, but also allows us to aknowlegde that Gregor Mendel gave future scienctists the chance to learn how to manipiulate genes. The molecular basis of inheritance is now better understood, thanks to him. ...read more.

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