Monohybrid Problems: Solve and show Work!!!!
1)
Long eyelashes are dominant over short eyelashes. Determine the genotypes for each of the following:
A. Homozygous Dominant __________________________________
B. Heterzygous ________________________________________
C. True-bred short eyelashes _____________________________________
D. His/Her Dad had long and mom short eyelashes ____________________________
E. Homozygous recessive ___________________________________
2. Curly hair is dominant over straight hair. Sue has straight hair and Joe is heterozygous for the trait. What will the
genotypes and phenotypes of their offspring be?
3. If dimples are a dominant trait and Gene is homozygous recessive and Beulah doesn’t have dimples. Can any of
their kids have dimples? (show cross to prove)
4. Short tails are dominant over long tails in rabbits. What will the genotype and phenotype of the offspring from a
cross between a homozygous dominant and homozygous recessive rabbit be?
5. In humans cystic fibrosis is a recessive trait. Ellen is homozygous dominant (normal) for the gene. Peter is a
carrier for cystic fibrosis disease. Being a carrier means one is normal but carries the recessive allele, in other words,
carriers are heterozygous. What are the odds that their children will be afflicted with cystic fibrosis?
6A. Freckles are dominant over no freckles. Determine the genotype and phenotype of the parents if none of the
kids have freckles.
6B What would the genotype and phenotype of the parents be if half of the kids had freckles and the other half did
not?
7. Reprove Mendel’s Principle of Segregation!! Tongue rollers are dominant over non-rollers. Garth is homozygous
dominant and Paula is a non-roller. Determine genotypes, phenotypes and their ratios of the F-1 and F-2
generations from their possible.