Name: ___________________________________________________ Date:_______________________ Advanced Biology Genetics Test Multiple Choice 1. In cattle, roan color (mixed red and white hairs) occurs in the heterozygous (Rr) offspring of red (RR) and white (rr) homozygotes. What type of dominance does this demonstrate? a. Codominance b. Complete dominance c. Incomplete dominance d. Sex linked trait Refer to the information below to answer the following questions. An achondroplastic male dwarf marries a woman of average height. The man’s father was six-feet tall, and both the woman’s parents were of average height. Achondroplastic dwarfism is autosomal dominant. If a child inherits two dominant alleles (AA) it does not survive past the first year. 2. How many of their children might be expected to have achondroplasia? a. 0% b. 25% c. 50% d. 100% 3. How many of their children might have a genotype of AA? a. 0% b. 25% c. 50% d. 100% 4. How many of their children might have a genotype of Aa? a. 0% b. 25% c. 50% d. 100% 5. How many of their children might be of average height? a. 0% b. 25% c. 50% d. 100% Refer to the information below to answer the following questions. A normal vision man marries a color-blind woman. Red-green color blindness is X-lined recessive. 6. How many daughters might be expected to be color-blind? a. All b. None c. Half d. One out of four 7. How many sons might be expected to be color-blind? a. All b. None c. Half d. One out of four 8. A couple has three children, all of whom have blond hair. One parent is a blond (rr) and the other is a redhead (Rr). What is the probability that their next child will be a redhead? a. ¼ b. ½ c. ¾ d. 1 (4/4) Fill In For the sex-linked gene of baldness, the alleles are given in the chart below. Allele Trait X = Normal Xb = Bald (recessive) Y = Normal For the case of a normal male and a bald female, fill out the Punnett square below and then answer the questions that follow. Draw a Punnett square below. What is the probability that their child will be: a. A bald female? _________ b. A female carrier? _________ c. A normal female who is not a carrier? _________ d. A bald male? _________ e. A normal male? _________ Suppose you crossed a heterozygous yellow pea plant (Yy) with a homozygous green pea plant (yy). What are the possible genotypes and phenotypes of the offspring? Use the Punnett square in Figure 1 to compute your answers. Y y Yy yy Yy yy Figure 1 Genotypes:____________ Phenotypes:____________ In Labrador retrievers coat color is determined by 2 genes that sort independently: melanin production (B for black is dominant to b for brown) melanin deposition (E for deposition is dominant to e for no deposition) Yellow Labrador retrievers may e homozygous dominant or heterozygous for pigment production but are homozygous recessive for melanin deposition. Chocolate Labrador ret.

1. Name:
___________________________________________________
Date:_______________________
Advanced Biology
Genetics Test
Multiple Choice
1. In cattle, roan color (mixed red and white hairs) occurs in
the heterozygous (Rr) offspring of red (RR) and white (rr)
homozygotes. What type of dominance does this demonstrate?
a. Codominance
b. Complete dominance
c. Incomplete dominance
d. Sex linked trait
Refer to the information below to answer the following
questions.
An achondroplastic male dwarf marries a woman of average
height. The man’s father was six-feet tall, and both the
woman’s parents were of average height. Achondroplastic
dwarfism is autosomal dominant. If a child inherits two
dominant alleles (AA) it does not survive past the first year.
2. How many of their children might be expected to have
achondroplasia?

2. a. 0%
b. 25%
c. 50%
d. 100%
3. How many of their children might have a genotype of AA?
a. 0%
b. 25%
c. 50%
d. 100%
4. How many of their children might have a genotype of Aa?
a. 0%
b. 25%
c. 50%
d. 100%
5. How many of their children might be of average height?
a. 0%
b. 25%
c. 50%

3. d. 100%
Refer to the information below to answer the following
questions.
A normal vision man marries a color-blind woman. Red-green
color blindness is X-lined recessive.
6. How many daughters might be expected to be color-blind?
a. All
b. None
c. Half
d. One out of four
7. How many sons might be expected to be color-blind?
a. All
b. None
c. Half
d. One out of four
8. A couple has three children, all of whom have blond hair.
One parent is a blond (rr) and the other is a redhead (Rr).
What is the probability that their next child will be a redhead?
a. ¼
b. ½

4. c. ¾
d. 1 (4/4)
Fill In
For the sex-linked gene of baldness, the alleles are given in the
chart below.
Allele Trait
X = Normal
Xb = Bald (recessive)
Y = Normal
For the case of a normal male and a bald female, fill out the
Punnett square below and then answer the questions that follow.
Draw a Punnett square below.
What is the probability that their child will be:
a. A bald female? _________
b. A female carrier? _________
c. A normal female who is not a carrier? _________
d. A bald male? _________
e. A normal male? _________
Suppose you crossed a heterozygous yellow pea plant (Yy) with
a homozygous

5. green pea plant (yy). What are the possible genotypes and
phenotypes of the
offspring? Use the Punnett square in Figure 1 to compute your
answers.
Y
y
Yy
yy
Yy
yy
Figure 1
Genotypes:____________ Phenotypes:____________
In Labrador retrievers coat color is determined by 2 genes that
sort independently:
melanin production (B for black is dominant to b for brown)
melanin deposition (E
for deposition is dominant to e for no deposition) Yellow
Labrador retrievers may e homozygous dominant or
heterozygous for pigment production but are homozygous
recessive for melanin deposition. Chocolate Labrador retrievers
are homozygous recessive for melanin production but may be
homozygous dominant or heterozygous for melanin
deposition.Black Labrador retrievers may be homozygous

6. dominant or heterozygous for melanin production and for
melanin production.
Write all possible genotypes for yellow, chocolate, and black
Labrador retrievers:
Yellow__________________
Chocolate__________________
Black___________________