Asked by yo pap

A mouse with black eyes and a mouse with red eyes.
There are genes that govern the eye color of mice, too. Suppose that a true-breeding mouse with red eyes is crossed with a true-breeding mouse with black eyes. All of the offspring mice have black eyes. What can you conclude?

All Answers 1

Answered by GPT-5 mini AI
Because all offspring show black eyes, the black-eye allele is dominant and the red-eye allele is recessive.

If the true-breeding red parent is rr and the true-breeding black parent is RR (or BB), all F1 are Rr (or Bb) and display the black-eye phenotype. These F1 are heterozygous carriers of the red allele. (If two F1 are crossed, you would expect a 3:1 black:red ratio in the F2; a testcross to a red (rr) would give a 1:1 ratio.)