Lesson 5Terminology Practice
Genotype and Phenotype
Aa
Genotype Phenotype
Wing Size
Brown Fur
Phenotype
Phenotype
Genotype
Phenotype
Phenotype
Dark coloring
Light Coloring
Xx
Genotype
Phenotype
Grey Fur
Orange Fur
Genotype
Tt tT tt
Tt Tt
TT
Genotype
Phenotype
Genotype
Yy
Hh
SS
Genotype
Phenotype
Tongue rolling
Phenotype
Having a Tail
Phenotype
Genotype
Phenotype
Genotype
Phenotype
TT Tt tt
Genotype
Genotype
Lesson 5Terminology Practice
Heterozygous and Homozygous
TT TtHeterozygousHomozygous
Xx
Heterozygous
UU
Homozygous
BB
Homozygous
Heterozygous
aA
Heterozygous
nn
Homozygous
Pp
Heterozygous
ii
Homozygous
lL
Heterozygous
Lesson 5Terminology Practice
Dominant and Recessive
Aa
Dominant
lL
Recessive
hh
Recessive
Will the trait be dominant or recessive?
Bb
Dominant
Will the trait be dominant or recessive?
zZ
Dominant
Will the trait be dominant or recessive?
bb
Recessive
Will the trait be dominant or recessive?
mm
Recessive
Will the trait be dominant or recessive?
Dominant
Will the trait be dominant or recessive?
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STOP!
For part 2 of genetics packet
Lesson 5Punnet Square Practice
Practice Problem 1 - Part 1
Earlobes have two forms.Unattached earlobes are dominant (E). Attached earlobes are recessive (e). The father is heterozygous. Question: What is his genotype?
Answer: His genotype is Ee because he is heterozygous.
Father E
e
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Mother
e e
E
e
MotherPractice Problem 1 - Part 2
Question: If the mother has attached earlobes, what is her genotype?
Answer: Her genotype must be ee because attached earlobes are recessive.
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Father
Father
Mother
e
E
e
EE
e
e e
e
ee e
Practice Problem 1 - Part 3
So the father is heterozygous (Ee)The mother is homozygous dominant (ee).
Question: What are the chances that their offspring will have attached earlobes?
Answer: There is a 50% chance because there are two boxes with the ee genotype.
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Father
Mother
D
D
D
Dd
d
D D
d
dd d
Practice Problem 2
Dimples are a dominant trait (D)Not having dimples is the recessive trait (d).A mother is homozygous dominant (DD)The father is homozygous recessive (dd).Question: What are the chances they have children with dimples.
Answer: 100% will have dimples because all possible children carry at least one dominant allele.
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Practice Problem 3
Freckles (F) are a dominant trait.Not having freckles is a recessive trait (f). Question: If mother is a heterozygous and a father is a homozygous recessive, what are the chances that their offspring will have freckles?
Answer: There is a 50% chance that their offspring will have freckles because the dominant allele appears half the time.
Mother
F
F
f
ff
f
F f
f
ff f
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