Download Monohybrid Problems

Name: __________________________
Monohybrid
Problems
1. If in pea plants, G=green pods and g = yellow pods, what would be the genotypic and phenotypic results
of this cross: Gg x GG.
Make your punnett square here:
1a. List ALL offspring genotypes AND their probabilities (Ex: Bb50%, BB-25%, bb-25%):
1b. List ALL offspring phenotypes AND their probabilities:
2. If in pea plants T=tall and t=short, what would be the genotypic and phenotypic results of this cross:
Tt x Tt
Make your punnett square here:
2a. Genotype probabilities:
2b. Phenotype probabilities:
3. Cross a white seed plant with a heterozygous brown seed plant. (You can figure this one out without
being told which allele is dominant. If the brown plant is heterozygous (2 different genes, one dominant
and one recessive), which gene must be dominant?)
Make your punnett square here:
3a. Genotype probabilities:
3b. Phenotype probabilities:
4. The genetic disease called cystic fibrosis is inherited through a recessive gene. If both parents are
heterozygous for this trait, what is the probability that they will have a child who suffers from this
disease?
Probability of child that suffers from the disease:
5. In cats, the gene for short hair is dominant over the gene for long hair (angora). A short-haired tom cat is
mated with an angora female. She bears eight kittens, six are short-haired and two are long-haired.
(*Remember, punnett squares indicate probabilities only. It is possible to BEAT THE ODDS…) Give
the genotype of the tom cat and the female.
5a. Genotype of tom cat:
5b. Genotype of female:
6. Some dogs bark while they are trailing an animal. Others are silent. The barking trait is inherited from a
dominant gene. A barker, who had a silent mother, is mated to a silent trailer. The female bears four
puppies. What are the chances that there will be silent puppies in this group?
Probability of silent pups:
7. Brown hair color is dominant to blond hair color. If two brown-haired parents have one blond-haired
child, what is the probability that their second child will have brown hair?
Probability of a brown-haired child: