Question 36
Directions: The table lists the hair color and genotype of six individuals where black hair is dominant over blond. Use the table to answer any questions that follow.
HAIR COLOR
Name Hair color Alleles
Mr. Johnson black homozygous
Mrs. Johnson blond homozygous
Mr. Valdez blond heterozygous
Mrs. Valdez black heterozygous
Mr. Ellwood black heterozygous
Mrs. Ellwood blond homozygous
If Mr. and Mrs. Johnson had four children together, what color of hair would the children likely have?
a
All 4 of the children would have black hair.
b
Only 3 of the children would have black hair, and 1 child would have blond hair.
c
All 4 of the children would have blond hair.
d
Only 2 of the children would have black hair, and 2 of the children would have blond hair.
The answer is c) All 4 of the children would have blond hair.
This is because both Mr. and Mrs. Johnson have homozygous alleles for blond hair, meaning they can only pass on blond hair alleles to their children.