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Johann Mendel
• Born July 22, 1822
• Born in present day Czech Republic
• Son of a peasant farmer
• Only son (2 sisters)
• Almost didn’t go to school– Poor– Father’s injury
Education
• 1841 - Philosophy Institute of Olomouc• 1843 - St. Thomas Monastery
– Augustinian Order– Took test to become teacher - failed
• 1851 - University of Vienna– Studied to teach Math and Biology– Became ill when he went to take test again
Early Work
• Curious about the characteristics of different species
• Started work with the color of mice hair
Pea Experiment
• 7 characteristics tested– position of the flowers on the stem – stem length– color of the unripe pod – shape of the ripe seed– color of the seed coat – shape of the ripe pod– color of the ripe seed
Pea Plants (cont.)
• First experimented with round seeds and wrinkled seeds
• Tried pure round seeds and pure wrinkled seeds next to each other
• Bred pure round seeds with pure wrinkled seeds and all came out round
• Next generation saw round seeds at a 3:1 with wrinkled seeds
Basics of Heredity
• Dominant trait (A) - trait that when combined purely with another pure opposite trait, will show up in the next generation
• Recessive Trait (a) - trait that when combined purely with another pure opposite trait, will not show up in the next generation
• Called the traits “factors”
Mendel’s Laws
• The Law of Segregation - Each parent carries 1 trait that are combined together during reproduction, even though only 1 shows
• Law of Independent Assortment - When parents with 2 different traits reproduce the inheritance of one trait does not affect the inheritance of the other, and chance decides which one does show up
• Law of Dominance - There will always be 1 dominant trait and 1 recessive trait.
End of Work
• Presented these findings in a paper called "Experiments in Plant Hybridization" to the Association for Natural Research twice
• Published by the association a little later• Work was unrenowned, too complicated• 1863 - became abbot of monastery• 1870 - Tornado took out greenhouse• Died Jan. 6, 1884
"My scientific labors have brought me a great deal of satisfaction, and I am convinced that before long the entire world will praise the result of these labors.”
Rediscovery
• 1900 3 scientist rediscovered– Carl Correns in Germany– Hugo de Vries in the Netherlands – Erich von Tschermak-Seysenegg in Austria
• Development of phenotype vs genotype– 1911, Wilhelm Johannsen
• Punnet Squares– Reginald Crundall Punnett
• Still accepted today
Summary
• Served as a monk in the Augustinian Order
• Discovered the concept of dominant and recessive traits
• Work wasn’t recognized until 25 years after his death
References
• http://www.mnsu.edu/emuseum/information/biography/klmno/mendel_gregor.html
• http://mendel.imp.ac.at/mendeljsp/biography/biography.jsp
• http://astro4.ast.vill.edu/mendel/gregor.htm• http://web.pdx.edu/~cruzan/Kid's%20Mendel
%20Web/Johann%20Mendel.htm• http://www.accessexcellence.org/RC/AB/
BC/Gregor_Mendel.php• http://www.strangescience.net/mendel.htm