MULTIPLE ALLELESPractice Problems

HAIR COLOR In humans, hair color is determined by

multiple alleles Black – B1 (B1B1, B1B2, B1B3, B1b) Brown – B2 (B2B2, B2B3, B2b) Blond – B3 (B3B3, B3b) Red – b (bb)

PROBLEM 1 A woman who has blond hair marries a

man with red hair. All of their children have blond hair. What is the fathers genotype?

PROBLEM 2 A man with a genotype B1B2 has what

color hair? A woman with genotype B2b has what

color hair?

Do a cross to determine the possible phenotypic and genotypic ratios of their first child.

EYE COLOR In humans, eye color is determined by

multiple alleles.

Brown – E1 Green – E2 Blue – E3 Red – e

PROBLEM 1 What are the possible GENOTYPES for

each eye color?

PROBLEM 2 Cross a male homozygous for green

eyes with a female whose genotype is E3e.

BLOOD TYPES In humans, blood type is determined by

multiple alleles

What are the 4 blood types?

What are the 4 blood genotypes?