Question

a scientist is studying fruit fly wings. straight wings are dominant, curly wings are recessive. which statement correctly describes the f1 generation of a straight-winged parent is crossed with a curly winged parent and if both parents are true breeding?

Answer 1

If both parents are true breeding, they have two of the same allele and are homozygous.

Let's use S for the dominant allele and s for the recessive allele. We will end up with the following combinations:

$\left[\begin{array}{ccc}&S&S\\s&Ss&Ss\\s&Ss&Ss\end{array}\right]$

As you can see from the cross above, all of the offspring will be heterozygous for this allele. Therefore, all of the offspring will display the dominant phenotype (straight-winged).

Answer 2

Wouldn't the straight wings be more of the outcome sense those are dominant and only a few outcomes as in F2 g. be curly sense those are recessive.