Download Name: Date: Period: ______ Homework: Punnett Squares 1. In flies

Name: ____________________________
Date: _____________________
HOMEWORK: PUNNETT SQUARES
1. In flies, red eyes (R) are dominant to brown eyes (r). A heterozygote
fly is crossed with homozygous recessive fly.
a. What percentage of offspring will have brown eyes? ___________
b. What fraction of offspring will be heterozygotes? ___________
2. In a plant species, long stems (L) are dominant to short stems (l).
A heterozygous plant is crossed with a homozygous dominant plant.
a. What percentage of offspring will have short stems? ___________
b. What will be the ratio of genotypes in the offspring? _________________
3. In a species of mammals, gray fur (G) is dominant to white fur (g).
Two heterozygous mammals are mated together and produce offspring.
a. What fraction of offspring will have gray fur? ___________
b. What percentage of the offspring will be white fur? ___________
4. In plants, being short (t) is recessive to the tall allele (T).
A heterozygous plant is crossed with a short plant.
a. What will be the ratio of tall plants to short plants? _______________
b. What fraction of offspring will be homozygous recessive? ___________
5. In a certain animal, green eyes (B) are dominant and blue eyes (b) are
recessive. A heterozygote is mated with a blue eyed animal.
a. What fraction of offspring will have blue eyes? ___________
b. What percentage of the offspring will be heterozygotes? ___________
6. In flies, small wings (w) are recessive to large wings (W). A
homozygous dominant fly is mated with a homozygous recessive fly.
a. What percentage of offspring will have a Ww genotype? ___________
b. What percentage of offspring will have small wings? ___________
7. In a plant species, purple flowers (P) are dominant to white flowers (p).
Two heterozygotes for flower color are crossed to produce offspring.
a. What fraction of offspring will have purple flowers? ___________
Period: ______
8. Having attached earlobes (e) is recessive to unattached earlobes (E).
A man with genotype (Ee) and a woman with attached earlobes have a child.
a. What is the percent chance the child has attached earlobes? _________
b. What fraction of this couple’s children are likely to be genotype Ee? _________
9. In cats, long hair (H) is dominant to short hair (h). A cat with long hair (Hh)
is mated with a cat that also has long hair (Hh).
a. What fraction of offspring will have short hair? ___________
b. What will be the ratio of long hair to short hair? _________________
10. In pigeons, normal feathers (F) is dominant to frizzy feathers (f).
A heterozygote is crossed with a homozygous recessive bird.
a. What fraction of offspring will have normal feathers? ___________
b. What percentage of the offspring will have genotype (ff)? ___________
11. In pea plants, yellow peas (g) are recessive to green peas (G).
Two plants with yellow peas are crossed together.
a. What percentage of offspring will have yellow peas? ___________
b. What percentage of offspring will be heterozygotes? ___________
12. In flies, the allele for brown bodies (B) is dominant to yellow bodies (b).
Two flies with brown bodies (Bb) are mated to produce offspring.
a. What will be the ratio of brown to yellow bodies? ___________
b. What fraction of the offspring will have brown bodies? _______________
13. In a species of bird, short beaks (l) are recessive to long beaks (L). A bird
that is heterozygous for beak length is crossed with a short beaked bird.
a. What percentage of offspring will have long beaks? ___________
b. What will be the ratio of phenotypes in the offspring? _______________
14. In a certain plant, white flowers (p) are recessive to purple flowers (P).
A plant with purple flowers (Pp) is crossed with a plant with white flowers.
a. What percentage of offspring will have purple flowers? ___________
b. What will be the ratio of genotypes in the offspring? _______________
c. What fraction of the offspring will have white flowers? ___________