Question: GregorMendel, an Austrian monk who lived from 1822 to 1884 in what is now the Czech Republic, is widely considered the father of modern genetics for his scientifi c experiments and observations regarding genetic inheritance of pea plants. Between 1856 and 1863, Mendel meticulously cultivated and tracked approximately 29,000 pea plants ( Pisum sativum ). He studied the following seven characteristics in his pea plants:
(1) color and smoothness of the seeds (gray and round or white and wrinkled),
(2) color of the cotyledons (yellow or green),
(3) color of the fl owers (white or violet),
(4) shape of the pods (full or constricted),
(5) color of unripe pods (yellow or green),
(6) position of fl owers and pods on the stems (axial or terminal), and
(7) height of the plants (short or tall).
Essentially, Mendel was studying seven different genetic loci, each possessing two different alleles. Mendel 's work found that hybridization of plants possessing dominant and recessive traits (alleles) produced a ratio of one-quarter purebred dominant, one-half hybrid, and one-quarter purebred recessive traits in their offspring. The dominant trait hid the recessive trait in plants containing hybrid traits. If a dominant trait is represented by the capital letter ‘ A 'and a recessive trait by the lowercase letter ‘ a, ' then a hybrid is represented by an ‘ Aa. ' In February and March 1865, Mendel described his experiments in a two-part paper titled ‘ Experiments on Plant Hybridization ' that he read to the Natural History Society of Brno. Mendel's paper was published in German the following year in the proceedings of the society with the title ‘ Versuche ü ber Pfl anzen-Hybriden. ' His work was ignored for 35 years until it was rediscovered in 1900 by three European scientists. Thomas Hunt Morgan later connected Mendel's theories with his chromosomal inheritance theory and thus brought Mendel's work into the mainstream of modern genetics.
Sources: http://www.mendelweb.org/Mendel.html
- http://en.wikipedia.org/wiki/mendelian_inheritance