Question

Red-green colorblindness is a inherited disorder in which individuals have trouble distinguishes

Answer 1

Since the colorblindness is located on the X chromosome, the man must have inherited his colorblindness from his mother.

X-linked traits

Women are XX while men are XY.

Also, the X chromosome in XY always comes from the mother.

Since the man is affected for colorblindness but his brother is not, it means that only one X chromosome of the mother is affected while the father can be affected or otherwise.

Assuming the father is free from colorblindness and the allele is represented by c:

          $X^cX$    x    $XY$

      $X^cX$    $X^cY$    $XX$    $XY$

Thus, the man's genotype is  $X^cY$ and it comes from the mother.

More on X-linked traits can be found here: brainly.com/question/9830755