Unattached earlobes are dominant to attached earlobes. cleft chin is dominant to no cleft. parents that are heterozygous for both traits are crossed. determine the ratios of offspring with: unattached earlobes and cleft chin : unattached earlobes and no cleft : attached earlobes and cleft chin : attached earlobes and no cleft :

Unattached earlobes and cleft chin : 9

Unattached earlobes and no cleft : 3

Attached earlobes and cleft chin : 3

Attached earlobes and no cleft :1

Explanation:

Given -

Unattached earlobes are dominant to attached earlobes

Let the allele for attached ear lobe be represented by "l" and and unattached ear lobe be represented by "L"

Cleft chin is dominant to no cleft.

Let the allele for cleft chin be represented by "C" and no cleft chin be represented by "c"

Genotype of heterozygous parents

LlCc X LlCc

LC          Lc     lC         lc

LCLLCCLlCc     LlCCLlCc

LcLLCcLLcc    LlCcLlcc

lCLlCCLlCc    llCCllCc

lcLlCc         Llcc    llCcllcc

LLCC - 1

LlCc – 5

LlCC-2

LLCc – 1

LLcc-1  

Llcc -2

llCC-3

llcc-1

Unattached earlobes and cleft chin : 9

Unattached earlobes and no cleft : 3

Attached earlobes and cleft chin : 3

Attached earlobes and no cleft :1