Human Heredity 11th Edition by Michael Cummings

Exercise 34

Determine the possible genotypes of the following parents by analyzing the phenotypes of their children. In this case, we will assume that brown eyes (B) is dominant to blue (b) and that right-handedness ( R ) is dominant to left-handedness ( r ).
A) Parents: brown eyes, right-handed × brown eyes, right-handed
Offspring: 3/4 brown eyes, right-handed
1/4 blue eyes, right-handed
B) Parents: brown eyes, right-handed × blue eyes, right-handed
Offspring: 6/16 blue eyes, right-handed
2/16 blue eyes, left-handed
6/16 brown eyes, right-handed
2/16 brown eyes, left-handed
C) Parents: brown eyes, right-handed × blue eyes, left-handed
Offspring: 1/4 brown eyes, right-handed
1/4 brown eyes, left-handed
1/4 blue eyes, right-handed
1/4 blue eyes, left-handed