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After going over some basic concepts as a class, we started doing our own experiaments. I first looked at purple eyes (PR) and dumpy wings (DP) individually and together, and the results were similar to the experiments that we did as a class, so I chose other traits. I tried a female that had no wings (AP) and was tan (T), with a wild type male.

Female (AP;T) with Male (+) Offspring:

Female (+): 487

Male (T): 586

In the first cross, all the males were tan and all the females were wild type. Then, I crossed the offsring:

+: 413

AP: 128

T: 376

AP;T: 127

I wanted to explore this more with the gender, so I tried the same two traits on a male with a wild type female

Female (+) with Male (AP;T) Offspring:

+: 1066

All of the offspring in the first round were (+). Then I crossed the offspring:

Female (+): 378

Male (+): 200

Female (AP): 111

Male (AP): 71

Male (T): 184

Male (AP;T): 50

I needed to look at the traits individually to make sense of this. I started with T, because that one seemed to be linked to sex.

Female (T) with Male (+)

Female (+): 486

Male (T): 484

Again, all the males in the first round were tan, and all the females were wild type. I crossed the offspring:

Female (+): 256

Male (+): 282

Female (T): 234

Male (T): 241

Then, I tried the same thing with a tan male.

Female (+) with Male (T)

+: 1016 (all offspring wild type)

Then, I crossed the offspring:

Female (+): 503

Male (+): 278

Male (T): 251

All the females were wild type, while half of the males were tan and half were wild type. I believe that T is and X-linked trait. When just the mother is tan, she will pass the trait to her sons because the only X-chromosome they get is from her, while her daughters will be tan (if the trait is recessive), because they also get an X-chromosome from their father (if he is wild type). When the offspring are crossed, because the male is tan and the females have one X from their tan mother, this generation would be even. When just the father is tan, none of his children will be tan, because he will not pass the X-chromosome to his sons, and his daughters get another X-chromosome. However, when the offspring are crossed, because the daughters got an X-chromosome from their tan father, they would pass this on to half of their sons.