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Gregor Mendel: Grandfather of Genetics PowerPoint Presentation
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Gregor Mendel: Grandfather of Genetics

Gregor Mendel: Grandfather of Genetics

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Gregor Mendel: Grandfather of Genetics

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  1. Gregor Mendel: Grandfather of Genetics www.assignmentpoint.com

  2. Mendel • Modern genetics had its beginnings in an abbey garden, where a monk named Gregor Mendel documented a particulate mechanism of inheritance. • He discovered the basic principles of heredity by breeding garden peas in carefully planned experiments. • His approach to science had been influenced at the University of Vienna by one of his professors: the physicist Doppler. www.assignmentpoint.com

  3. Mendel’s work • In order to study inheritance, Mendel chose to use peas, probably as they are available in many varieties. • The use of plants also allowed strict control over the mating. • He chose to study only characters that varied in an ‘either-or’ rather than a ‘more-or-less’ manner. www.assignmentpoint.com

  4. Genetic crosses • To hybridise 2 varieties of pea plants, Mendel used an artist’s brush. • He transferred pollen from a true breeding white flower to the carpel of a true breeding purple flower. www.assignmentpoint.com

  5. Tracking heritable characteristics • Mendel tracked heritable characters for 3 generations. • When F1 hybrids were allowed to self-pollinate a 3:1 ratio of the 2 varieties occurred in the F2 generation. www.assignmentpoint.com

  6. Mendel’s law of segregation • By carrying out these monohybrid crosses, Mendel determined that the 2 alleles for each character segregate during gamete production. • Mendel discovered this c.1860. • DNA was not discovered until 1953. www.assignmentpoint.com

  7. Mendel’s terminology • True breeding: When the plants self-pollinate, all their offspring are of the same variety. • Hybridisation: Mating, or crossing, of two varieties. • Monohybrid cross: A cross that tracks the inheritance of a single character. • P generation: True breeding parents. • F1 generation: (first filial) Hybrid offspring of the P generation. • F2 generation: (second filial) Offspring from the self-fertilisation of the F1 hybrids. www.assignmentpoint.com

  8. Mendel’s impact • Mendel’s theories of inheritance, first discovered in garden peas, are equally valid for figs, flies, fish, birds and human beings. • Mendel’s impact endures, not only on genetics, but on all of science, as a case study of the power of hypothesis/deductive thinking. www.assignmentpoint.com