AA, AO=type A
BB, BO= TYPE B
AB= TYPE AB
OO= TYPE O
QUIZ 3: MENDELIAN EXCEPTIONS
PROBLEM ANALYSIS
Read and analyze each problem and write your answer with solution on your quiz notebook.
INCOMPLETE DOMINANCE
1. A red carnation is crossed with a pink carnation.
a. What are the genotypes of the parents? ( 1 point)
b. Draw a Punnett square for this cross. ( 2 points)
c. What is the genotypic and phenotypic ratio of the offspring? (2 points)
2. In squirrel, teeth can be long, short or medium sized. The allele for long teeth is (L) and the allele for short teeth is (l). Imagine a long-toothed squirrel was crossed with a short-toothed squirrel.
a. What are the genotypes of the parents? ( 1 point)
b. Draw a Punnett square for this cross. ( 2 points)
c. What is the genotypic and phenotypic ratio of the offspring? (2 points)
3. Coat color in mice is incompletely dominant. Yellow and white-colored mice are homozygous, while cream-colored mice are heterozygous. If two cream-colored mice mate.
a. What are the genotypes of the parents? ( 1 point)
b. Draw a Punnett square for this cross. ( 2 points)
c. What is the genotypic and phenotypic ratio of the offspring? (2 points)
4. In radishes, red and white are pure-breeding colors, while hybrids are purple. If a red radish is crossed with a white radish.
a. What are the genotypes of the parents? ( 1 point)
b. Draw a Punnett square for this cross. ( 2 points)
c. What is the genotypic and phenotypic ratio of the offspring? (2 points)
CODOMINANCE
5. Roan cattle are the heterozygous hybrids of a cross between a white bull and a red cow. If a roan bull were crossed with a red cow.
a. What are the genotypes of the parents? ( 1 point)
b. Draw a Punnett square for this cross. ( 2 points)
c. What is the genotypic and phenotypic ratio of the offspring? (2 points)
6. In a certain fish, blue scales and red scales are codominant. When a fish has the genotype B R, it has a patchwork of blue and red scales. What happens if you breed this fish with a fish that only has blue scales?
a. What are the genotypes of the parents? (1 point)
b. Draw a Punnett square for this cross. (2 points)
c. What is the genotypic and phenotypic ratio of the offspring? (2 points)
7. In chickens, black and white feather color are codominant alleles for this trait. Show a cross between two black and white feathered chickens (erminette).
a. What are the genotypes of the parents? (1 point)
b. Draw a Punnett square for this cross. (2 points)
c. What is the genotypic and phenotypic ratio of the offspring? (2 points)
MULTIPLE ALLELES
8. Mom has type A blood. Dad has type AB blood. What possible blood types could their children inherit? (Show all possibilities).
