bio (0301) - BoL: gregor mendel

an austrian monk living in a monastery in what is now czechoslovakia. he published his findings about genetics in 1865, but his work was not realized until 1900. nowadays he is known as the father of genetics.

for years mendel tested the breeding of certain characteristics among peas.

his method worked because he tested for only one variable at a time, with only 2 possible outcomes, with no intermediates. he used purebred varieties to ensure validity, and used many peas of each kind per trial. his findings used numbers and statistics, which wasn't common among biologists at the time, but it made his findings better understood.

he tested factors such as:

tall x short
axial x terminal flowers
smooth x constricted pods
round x wrinkled seeds

his findings were that usually, the results in the 2nd generation after the purebred parrents favoured one characteristic over the other in a ration of 3:1. he realized that this is because one "factor" was dominant over the other.

consider an example tall (T) peas bred with short (s) peas

there are 4 possibilities of "factor" (allele) combinations:

TT Ts sT ss

since tall (T) is dominant, the three results with a T in them will result in tall peas, where as only the ss pea variety would result in short-stemmed peas.