It may be c, if not you can punch me in the face.
Answer:
The genes are linked, and the arrangement is coupled (one homolog has both dominant alleles; the other homolog has both recessive alleles).
RY
/
ry
Explanation:
R_= colored aleurone
rr= colorless aeurone
Y_= green plant
yy= yellow plant
They do a testcross between a plant of unknown genotype and phenotype and a plant that is homozygous recessive for both traits (yr/yr) the following F1 is obtained:
- 88 Colored, green (RY/ry)
- 92 colorless, yellow (ry/ry)
- 8 colorless, green (rY/ry)
- 12 colored, yellow (Ry/ry)
If the genes assorted independently, all of the possible offspring phenotypes would appear in the same frequency. However, they obtained 2 phenotypes much more abundant that the other two. Since recombination is a rare event during crossing over, when two genes are linked the recombinant gametes are produced less frequently than the parentals.
We can propose that the phenotypes Colored, green (RY) and colorless yellow (ry) are the parental gametes, and the unknown plant has the arrangement RY/ry, with both genes linked.
There were 16 grasshoppers
