Question

each of two parents has the genotype brown/blond, which consists of the pair of alleles that determine hair color, and each parent contributes one of those alleles to a child. assume that if the child has at least one brown allele, that color will dominate and the child’s hair color will be brown.
a. list the different possible outcomes. assume that these outcomes are equally likely.
b. what is the probability that a child of these parents will have the blond/blond genotype?
c. what is the probability that the child will have brown hair color?

a. list the possible outcomes.
a. brown/blond and blond/brown
b. brown/brown and blond/blond
c. brown/brown, brown/blond, and blond/blond
d. brown/brown, brown/blond, blond/brown, and blond/blond
b. the probability that a child of these parents will have the blond/blond genotype is
(round to two decimal places as needed.)

Explanation:

Part a

Each parent has alleles brown (let's denote as \( B \)) and blond (denote as \( b \)). When they contribute alleles to the child, the possible combinations are: parent 1 gives \( B \) and parent 2 gives \( B \) (brown/brown), parent 1 gives \( B \) and parent 2 gives \( b \) (brown/blond), parent 1 gives \( b \) and parent 2 gives \( B \) (blond/brown), parent 1 gives \( b \) and parent 2 gives \( b \) (blond/blond). So all four combinations are possible.

Step1: Determine total possible outcomes

From part a, we know there are 4 possible outcomes (brown/brown, brown/blond, blond/brown, blond/blond), and each is equally likely.

Step2: Determine favorable outcomes for blond/blond

There is 1 favorable outcome (blond/blond).

Step3: Calculate probability

Probability is the number of favorable outcomes divided by total outcomes. So probability \( P=\frac{1}{4} = 0.25\).

Step1: Determine total possible outcomes

Total outcomes are 4 (from part a).

Step2: Determine favorable outcomes for brown hair

Brown hair occurs when there is at least one brown allele. The genotypes with brown hair are brown/brown, brown/blond, blond/brown. So there are 3 favorable outcomes.

Step3: Calculate probability

Probability \( P=\frac{3}{4}= 0.75\).

Answer:

D. brown/brown, brown/blond, blond/brown, and blond/blond

Part b