Question

Color-blindness (b) is a recessive sex-linked disorder, in which the proteins that absorb red and green light in the eye do not work. Identify the following phenotypes using the provided terms.

a. X^b X^b
b. X^b X^b

Answer 1

The phenotype for an individual with two X chromosomes indicated as X^b X^b is female colorblindness, as the disorder is sex-linked recessive, meaning a female needs two copies of the allele to express the condition.

Step-by-step explanation:

Color-blindness, specifically red-green colorblindness, is a sex-linked recessive disorder affecting the ability to distinguish between red and green colors. The phenotypes for individuals with two sex chromosomes represented as X^b X^b would indicate that these individuals are female and have two copies of the colorblindness allele. Since colorblindness is recessive, the phenotype expressed is female colorblindness. It is important to correct the misconception presented in the question, as males cannot be carriers of an X-linked recessive trait in the traditional sense because they only have one X chromosome; thus, any X-linked recessive allele they possess would result in expression of the trait.