Question

the image shows a cross between a father and a mother who are carriers for a genetic disease. what are the chances of one of their children developing the disease? 0 ¼ ½ ¾

Explanation:

Step1: Set up the Punnett - square

The parents are both carriers with genotype Rr. The possible gametes from each parent are R and r.

Step2: Fill in the Punnett - square

	R	r
r	Rr	rr

Step3: Determine the genotypes of offspring

RR is unaffected non - carrier, Rr is unaffected carrier, and rr is affected.

Step4: Calculate the probability

Out of 4 possible genotypes (RR, Rr, Rr, rr), 1 is rr (affected). So the probability is $\frac{1}{4}$.

Answer:

$\frac{1}{4}$