A BRIEF HISTORY OF GENETICS


A BRIEF HISTORY OF GENETICS :
Scientists made several landmark discoveries about genetics during the 19th and 20th centuries. The study
of heredity—the way in which traits are passed from one generation to the next—began with an Austrian
monk named Gregor Mendel (1822—1884). Mendel watsan amateur gardener. Working in a monastery in Brenner (now Brno in the Czech Republic), lie noticed that some plants produced offspring that had smooth, round peas, while other peas were rough and wrinkled. There were short plants as well as tall varieties, yellow peas as well as green ones.
              Mendel spent seven years observing in great detailhow these characteristics were transferred from one generation to the next. He caine to the conclusion that certain deciding principles or “factors” determine whether a Plant’s offspring will be tall or short, wrink led or smooth. He also discovered that the offspring receives two copies of each factor, one from each pare nt. He noted that some factors were dominant over others. Rather than the stronger and weaker traits blending, the dominant factor showed up in the offs
pring. We call Mendel’s “factors” genes. In 1865 Mendel presented his theories to the local scie
nce society in Brunn, but his ideas were not accepted as the brilliant discoveries that they were. When Mendel died in 1884, little of his work was remembered.
              In 1900. however, three scientists, working independ ently in three different countries, came to the same conclusions about heredity that Mendel had. These men were Hugo de Vries in the Netherlands, Karl Correns in Germany. and Erich von Tschermak in Austria. Eventually, ea:h scientist credited Mendel as the true discoverer of the principles of heredity.

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