Name________________________________________Date_______________Per______
SINGLE FACTOR CROSSES # 1
Use the following key: DOMINANT
RECESSIVE
dimples (D)
no dimples (d)
long eyelashes (L) short eyelashes (l)
freckles (F)
no freckles (f)
Cross Dd x DD
Complete a Punnett Square
What is the genotypic ratio? ______________
What is the phenotypic ratio? ______________
Cross Ff x Ff
Complete a Punnett Square
What is the genotypic ratio? ______________
What is the phenotypic ratio? ______________
Cross Ll x ll
Complete a Punnett Square
What is the genotypic ratio? ______________
What is the phenotypic ratio? _____________
Cross a homozygous long lashes with a heterozygous long lashes.
What is the genotype of each person? ____________
Complete a Punnett Square.
How many genotypes are possible? ____________
What is the genotypic ratio? ____________
How many phenotypes are possible? ____________
What is the phenotypic ratio? ____________
Genetics 1 C Layer #20
Revised 4/9/10
Cross a homozygous freckled person with a person who has no freckles.
What is the genotype of each parent? ____________
Complete a Punnett Square.
What is the genotypic ratio? ____________
What is the phenotypic ratio? ____________
A heterozygous dimpled man marries a woman with no dimples.
What is the genotype of each parent? ____________
Complete a Punnett Square.
What percentage of their children do
you expect to have dimples? ____________
What percentage of their children do
you expect to have dimples? ____________
A heterozygous dimpled man marries a heterozygous dimpled woman.
What is the genotype of each parent? ____________
Complete a Punnett Square.
What percentage of their children do
you expect to have dimples? ____________
What percentage of their children do
you expect to have dimples? ____________
What is the chance that the offspring will
be heterozygous for dimples? ____________
What is the chance that the offspring will
be homozygous for dimples? ____________
Genetics 1 C Layer #20
Revised 4/9/10