Question

sickle cell anemia is an inherited disease in which red blood cells become distorted and deprived of oxygen. a person with two sickle cell genes will have the disease, but a person with only one sickle cell gene will have a mild, non - fatal anemia called sickle cell trait. using s to represent a healthy gene, and s the sickle cell gene, the table shows the four possibilities for the children of two ss parents. find the probability that these parents give birth to a child who has sickle cell trait. \

$$\begin{tabular}{|c|c|c|} \\hline & \\multicolumn{2}{|c|}{second parent} \\\\ \\hline first parent & s & s \\\\ \\hline s & ss & ss \\\\ \\hline s & ss & ss \\\\ \\hline \\end{tabular}$$

$p$(child has sickle cell trait) = \boxed{} (simplify your answer.)

Explanation:

Step1: Identify total outcomes

The table has 4 cells (SS, Ss, sS, ss), so total possible outcomes = 4.

Step2: Identify favorable outcomes

Sickle cell trait is when there's 1 sickle cell gene (Ss or sS). From the table, Ss and sS are the favorable cases. Count of favorable outcomes = 2.

Step3: Calculate probability

Probability = $\frac{\text{favorable outcomes}}{\text{total outcomes}}$ = $\frac{2}{4}$ = $\frac{1}{2}$.

Answer:

$\frac{1}{2}$