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Remote Ready Biology Learning Activities has 50 remote-ready activities, which work for either your classroom or remote teaching.
Mendelian Flies
Crystal, Luisana, and Eri
In general, we were trying to find how and whether sex linked breeding had an effect on the population. We initially believed that the breeding population will follow the Punnett squares that we constructed and the homozygous dominant (TT) would more often than not mask the recessive traits.
However, after several trials using different genes that yeilded results matching the punnett squares that we drew out as predictions, we came across a combination that broke the pattern. We had crossed a curly winged (CY) female with a wild type male (+) which gave 50/50 offspring. However, when we bred heterozygous flies, we found that instead of the expected 3:1 ratio, the breeding yeilded 2 curlywinged flies, and 1 wild type fly. In other words, the curly wing gene turned out to be the dominant. Furthermore, the fly that would have been homozygous dominant did not appear - CY is a lethal dominant resulting in the abortion of that offspring.