Question

use the following information for questions 16-19.
the gene for color vision is found only on the x chromosome. normal color vision is dominant to the recessive trait of being colorblind.
for 16-17, cross a colorblind female with a normal vision male.
for 18-19, cross a carrier female with a colorblind male.

question 16
1 pts
cross a colorblind female with a normal vision male. what is the genotype ratio of the offspring?
○ 2 xnxn: 2 xny
○ 2 xnxn: 2 xny
○ 2 xnxn: 2 xny
○ 2 xnxn: 2 xny

Explanation:

Step1: Define parent genotypes

Colorblind female: $X^nX^n$; Normal male: $X^NY$

Step2: Set up Punnett square

	$X^n$	$X^n$
$Y$	$X^nY$	$X^nY$

Step3: Count offspring genotypes

2 $X^NX^n$, 2 $X^nY$

Answer:

2 XNxn: 2 XnY