Question

In a cross between individuals of a species of tropical fish, all of the male offspring have long tail fins, and none of the females possess the trait. mating two of the resulting offspring fails to produce females with the trait. draw the punnett square for this.

Answer 1

In this cross the trait of long tail fins is associated with the “Y” chromosome of the male.  

Thus the alleles  of the male are represented by XY” where X chromosome has no trait of long tails find  

And the allels of the female are represented by XX, as they do not have long tail fins.  

When these two are crossed , the following punnet square is produced

X     Y”

X X X    X Y”

X X X     X Y”

The XX is the female while the XY” is the male offspring.