Unit 1: Genetics Quiz Review
1. Who is revered as the Father of Genetics?
a. Which types of plants did he study?
2. What were some interesting observations he made about his plants?
3. How is all genetic information stored?
a. Where is it all stored? (Which organelle?)
4. Define the following terms:
a. Gene
b. Trait
c. Allele
5. Provide an example of each:
a. Gene
b. Allele
6. Explain the Principle of Dominance
7. Define and give examples of each:
a. Dominant Traits
b. Recessive Traits
8. Explain the two Laws of Genetics:
a. Law of Segregation
b. Law of Independent Assortment
9. Describe the difference between Heterozygous and Homozygous. Provide examples to support your claim.
10. Identify which of the following are Heterozygous (He) or Homozygous (Ho)
BB ______
Gg ______
Aa ______
aa ______
FF ______
DD ______
Xx ______
pp ______
HH ______
yy ______
JJ ______
GG ______
Ff ______
Pp ______
Yy ______
11. Define the following terms:
a. Genotype
b. Phenotype
12. In a certain plant, tall stems (T) are dominant to short stems (t). A farmer crosses a short-stemmed plant with a
heterozygous long-stemmed plant. What are the expected genotypes, phenotypes, genotypic ratios, and
phenotypic ratios?
13. The alleles for hair color in guinea pigs are brown (B) and white (b). Write the possible genotypes for hair color
in guinea pigs and tell the phenotype for each.
14. In fruit flies, long wings (L) are dominant to short wings (l). Show the results of crossing a heterozygous long
wing fly with a Short winged fly.
15. Explain the difference between incomplete and co-dominance
16. Coat color in mice is incompletely dominant. Yellow and white-colored mice are homozygous, while creamcolored mice are heterozygous. If two cream-colored mice mate, what phenotypic ratio can we expect of their
offspring? Show the Punnett Square.
17. In snapdragons, flower color is controlled by incomplete dominance. The two alleles are red (R) and white (W).
The heterozygous genotype is expressed as pink.
a)
What is the phenotype of a plant with the genotype RR? ___________
b)
What is the phenotype of a plant with the genotype WW? ___________
c)
What is the phenotype of a plant with the genotype RW? ___________
18. A pink-flowered plant is crossed with a red-flowered plant. Show the Punnett Square. What is the probability of
producing a pink-flowered plant? ____%
Human blood types are determined by genes that follow the CODOMINANCE pattern of inheritance.
There are two dominant alleles (A and B) and one recessive allele (O).
19. Write the genotype for each person based on the description:
a.
b.
c.
e.
Homozygous for the “A” allele
Heterozygous for the “B” allele
Type O
Type “AB”
______
______
______
______
20. Draw a Punnett square showing all the possible blood types for the offspring produced by a type “A” mother and
an a Type “O” father
21. In shorthorn cattle, when a red bull (RR) is crossed with a white cow (WW), all the offspring are roan—a spotted,
red and white or milky red color. What offspring are expected from mating a roan bull and a red cow? Show the
Punnett Square.
22. If a roan bull were crossed with a white cow, what would be the possible phenotypes of their offspring? Show
the Punnett Square.
23. In fruit flies, the gene for white eyes is sex-linked recessive. (R) is red and (r) is white. Cross a white-eyed female
with a normal red-eyed male.
a. What percent of the males will have red eyes? White eyes?
b. What percent of the females will have red eyes? White eyes?
c. What total percent of the offspring will be white-eyed?
d. What percent of the offspring will be carriers of the white eye trait?
24. In humans, hemophilia is a sex-linked recessive trait. If a female who is a carrier for hemophilia marries a male
with normal blood clotting, answer the following questions.
a. What fraction of the female children will have hemophilia?
b. What fraction of the female children will be carriers?
c. What fraction of the male children will have normal blood clotting?
d. What fraction of the male children will be carriers?
e. What fraction of the male children will have hemophilia?
Use the following letters to represent Dominant and Recessive traits for hamsters. Black Fur (B) is Dominant
over Brown (b). Short fur (S) is dominant over Long (s).
25. A hamster that is homozygous for black, short fur is crossed with a hamster that is homozygous for brown,
long fur.
a.
Show the genotypes of the two hamsters in this cross ________ X ________
b.
Show the mating of two
_________________ X ________________
c. Show the phenotypic ratio:
d.
Show the genotypic ratio:
26. Show the mating of a hamster that is homozygous recessive for both coat color and coat length with one that is
heterozygous for both color and length.
a.
Show the genotypes of the two hamsters in this cross. ________ X ________
b.
Show the phenotypic ratio:
c.
Show the genotypic ratio:
27. A typical pedigree for a family that carries Falconi anemia. Note that carriers are not indicated with half-colored
shapes in this chart.
To answer questions #1-5, use the letter "f" to indicate the recessive Falconi anemia allele, and the letter "F" for
the normal allele.
a. What is Arlene's genotype?
b. What is George's genotype?
c. What are Ann & Michael's genotypes?
d. Most likely, Sandra's genotype is
.
e. List three people from the chart (other than George) who are most likely carriers of Falconi anemia.