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Cross a person who does not have freckles and is heterozygous for dimples with a person who has

freckles (but her mom does not) but no dimples.
1. What is the probability that these parents will have a child with dimples?
2. What is the probability that these parents will have a child with freckles?
3. What is the probability that these parents will have a child with dimples and freckles?

User Ibadia
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1 Answer

9 votes

Answer:

1. 1/2

2. 1/2

3. 1/4

Step-by-step explanation:

Let the allele for freckles be A or a while that of dimples be B or b.

A person without freckles but heterozygous for dimples = aaBb

A person who has freckles (whose mother has no freckles) but no dimples = Aabb

aaBb x Aabb

Offspring

4 AaBb - freckled and dimpled

4 Aabb - freckled and non dimpled

4 aaBb - non freckled and dimpled

4 aabb - non freckled and non dimpled

1. Probability that the parents will have a dimpled child = 8/16 or 1/2

2. Probability that they will have a child with freckles = 8/16 or 1/2

3. Probability that they will have a child with freckles and dimples = 4/16 or 1/4

See the attached image for the Punnet's square analysis of the cross

Cross a person who does not have freckles and is heterozygous for dimples with a person-example-1
User Karthik Nishanth
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