Final answer:
Offspring of two homozygous large-eyed black widows will all have large eyes, as they can only inherit the recessive 'e' allele. In fruit flies, the genotypes of offspring in an X-linked cross depend on the P generation's genotypes, resulting in various eye color ratios in the F1 and F2 generations.
Step-by-step explanation:
If a male black widow that is homozygous for large eyes (ee) mates with a female that is also homozygous for large eyes (ee), and considering that small eyes are dominant (E) and large eyes are recessive (e), all the offspring will have large eyes (ee). This is because the parents can only pass on the e allele to their offspring. As a result, the Punnett square would show that all possible combinations result in ee genotypes.
In an X-linked cross, such as the cross between a white-eyed male and a female that is heterozygous for red eye color in Drosophila (fruit flies), the genotypes of F1 and F2 offspring depend on whether the recessive trait was expressed by the male or the female in the P generation. When the P male expresses the white-eye phenotype and the female is homozygous red-eyed, all members of the F1 generation exhibit red eyes. A cross between a heterozygous red-eyed female and a white-eyed male, however, results in both red- and white-eyed females and males in different ratios based on the X-chromosome's inheritance patterns.