Transcript Set 3 - The Science Spot

T. Trimpe 2008 http://sciencespot.net/
Some people have dimples, while others do not. The presence of dimples is a
dominant trait (D), while not having dimples is recessive (d).
(1) Susie has dimples, but her husband, Tom, does not. Their first child has his
father's phenotype. What are the genotypes of the mother, father, and child?
Mother’s Genotype: _______
Father’s Genotype: _______
Son’s Genotype: _______
(2) What is the probability that a second child won’t have dimples? Create a
Punnett square to support your answer.
Some people have dimples, while others do not. The presence of dimples is a
dominant trait (D), while not having dimples is recessive (d).
(1) Susie has dimples, but her husband, Tom, does not. Their first child has his
father's phenotype. What are the genotypes of the mother, father, and child?
Dd
Mother’s Genotype: _______
dd
Father’s Genotype: _______
dd
Son’s Genotype: _______
(2) What is the probability that a second child
won’t have dimples? Create a Punnett square
to support your answer.
d
d
D Dd Dd
There would be a 50% probability that the
second child would not have dimples.
d
dd
dd