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AP BIOLOGY—Unit 5
Genetics
Name:
SHOW YOUR WORK!
T= tall
D= dimpled
F= freckles
t= short
d= no dimple
f= non-freckled
1. Give the expected genotype and phenotype ratios for each:
a. Tt x Tt
b. TT x tt
c. Tt x tt
d. TT x Tt
e. TT x TT
f. tt x tt
2. Give the genotype for the following possible phenotypes
a. a dimpled, freckled person
b. a non-dimpled, freckled person
c. a dimpled, non-freckled person
d. a non-dimpled, non-freckled person
3. The son of a homozygous dimpled man and a non-dimpled woman, marries a heterozygous
dimpled woman. What would be the expected genotypes and phenotypes of their offspring?
4. Give the expected genotypic and phenotypic ratios:
a. Dd Ff x ddFF
b. Ddff x ddFf
c. DdFf x DdFf
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Determine the possibility of each of the following genotypes or phenotypes from the cross given.
SHOW YOUR WORK!
1. Aa Bb Cc Dd x Aa Bb Cc Dd
a. Aa Bb Cc Dd
b. aa bb Cc Dd
c. AA Bb cc dd
d. Aa bb cc dd
e. an individual showing a dominant A, B and C traits, recessive D traits.
f. an individual showing dominant C and D traits and recessive A and B traits.
2. AA Bb cc Dd x aa Bb Cc DD
a. AA BB Cc Dd
b. Aa Bb Cc DD
c. Aa bb cc Dd
d. showing dominant A and D traits, recessive B and C traits.
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3. TT= tall
Tt=medium
B- brown eyed
tt= short (incomplete dominance)
b- blue eyed (complete dominance)
Give the expected genotype and phenotypic ratios.
a. BbTt x BbTt
b. BBTt x bbtt
c. BbTT x BBtt
d. bbTt x BBtt
4. In humans, brown eyes (B) are dominant to blue eyes (b). A brown-eyed woman marries a
blue-eyed man. What are the possible genotypes of the offspring?
5. The parents of a blue-eyed man are both brown-eyed. He marries a brown eyed woman, whose
father was brown eyed and whose mother was blue eyed. They have one child that is blue eyed.
What is the genotype of each individual mentioned?
6. B= black
b= blue
T= tall
t= short
A short blue bird is crossed with a tall black bird. Their offspring is a tall black bird. If this tall
black offspring is crossed with a heterozygous black short bird, what are the possible genotypes
and phenotypes of the offspring?
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7. Thalasemia is a disease of the blood. The dominant homozygous results in normal blood; the
heterozygous (Thalasemia minor) is treatable and the homozygous recessive results in
Thalasemia major which is fatal. Normal skin color results from a simple dominant gene, the
homozygous recessive is albino. What are the chances of the following if one parent is Normal
Blood, Heterozygous skin and the other is Thalasemia Minor, Albino?
a) Thalasemia major, normal skin
b) Normal blood, normal skin
c) Thalasemia minor, heterozygous skin
d) Thalasemia minor, albino
8. A=tall
D=deaf
a=short
B=brown eyed
b=blue eyed
C=see’s color c=color-blind
d=hearing
An AaBBCcDd is crossed with an AaBbCcDD, what is the expected frequency of an:
a)aaBbCcDd
b)AaBBccDd
c)aaBbccDD
d) a tall, brown-eyed, color-blind, deaf person?
e) a short, brown-eyed, seeing color, deaf person?