I need help with this practice question.
I'm assuming that would a epsitatic recessive question since the parents are true breeding and then the ratio would be 9.3.4. But I am not so sure.
Any help would be greatly appreciated thanks!
The Magenta variety is pure breeding, and hence must be homozygous at both loci, (Dominant at Gene A and recessive at Gene B), otherwise, in some of the generation along the family line, there would have been a non-magenta flower, which contradicts the pure breeding nature. But the same cannot be said for the pure breeding white variety, as it can still be homozygous recessive at Gene A and heterozygous at Gene B, it would still exhibit white flowers in all of its progeny after any number of generations.
But the fact that all the progeny of the cross between white and the magenta variety turns out to be red, removes the possibility of the white variety being heterozygous, as that would have produced atleast some magenta plants. Since all were red, we can be certain of the genotype of both the parents, and consequently of the F1 progeny.
This solves your first question. The second question needs the extrapolation of the information gathered while solving the first question into a Punnett square and a simple probability calculation. The third question is a factual question, but it must be mentioned, that this particular type of interaction can be classified under more than one type, and hence a single answer would not be possible for your third question.