Biology
Genetics Practice Problems
These worksheets are required before retaking quizzes.
Review/Practice Packet Mendelian (Prob. Set I)
1.
For each genotype, indicate whether it is
heterozygous (Het) or homozygous (HO)
AA _____ Bb _____ Cc _____ Dd _____
Pointed heads are dominant to round heads.
Ee _____ ff _____ GG _____ HH _____
pointed ____________
Ii ______ Jj ______ kk ______ Ll _____
pointed __________________
Mm ____ nn _____ OO _____ Pp ____
round
2.
For each of the genotypes below, determine the
phenotype.
Purple flowers are dominant to white flowers
4.
__________________
Set up the Punnett square for each of the crosses
listed below. The trait being studied is round seeds
(dominant) and wrinkled seeds (recessive)
PP ____________________________________
Rr x rr
Pp ____________________________________
pp ____________________________________
Round seeds are dominant to wrinkled
RR ____________________________________
Rr _____________________________________
What percentage of the offspring will be round? _______
rr _____________________________________
Brown eyes are dominant to blue eyes
Rr x Rr
BB _____________________________________
Bb _____________________________________
bb ______________________________________
Bobtails are recessive (long tails dominant)
TT ______________________________________
What
offspring
percentage of the
will be round? _______
Tt _______________________________________
tt ________________________________________
3.
RR x Rr
For each phenotype, list the genotypes. (Remember
to use the letter of the dominant trait)
Straight hair is dominant to curly.
straight ____________
straight____________
curly
What
offspring
percentage of the
will be round? ________
____________
Mrs. Loyd 
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Review/Practice Packet Mendelian (Prob. Set I)
Practice with Crosses. Show all work!
5.
A TT (tall) plant is crossed with a tt (short
plant).
What percentage of the offspring will be tall?
___________
6.
A Tt plant is crossed with a Tt plant.
What percentage of the offspring will be short?
11.Two plants, both heterozygous for the gene that controls
flower color are crossed.
What percentage of their offspring will have purple
flowers?
What percentage will have white flowers?
12. In guinea pigs, the allele for short hair is dominant
(SS).
What genotype would a heterozygous short
haired guinea pig have?
What genotype would a pure-breeding short haired
guinea pig have?
What genotype would a long haired guinea pig have?
7.
8.
A heterozygous round seeded plant (Rr) is crossed
with a homozygous round seeded plant (RR).
What percentage of the offspring will be homozygous
(RR)?
A homozygous round seeded plant is crossed with a
homozygous wrinkled seeded plant. What are the
genotypes of the parents?
13. Show the cross for a pure-breeding short-haired
guinea pig (SS) and a long haired (ss) guinea pig.
What percentage of the offspring will have short hair?
14. Show the cross for two heterozygous guinea pigs.
__________ x __________.
What percentage of the offspring will also be
homozygous?
What percentage of the offspring will have short hair?
What percentage of the offspring will have long hair?
9.
In pea plants purple flowers are dominant to white
flowers. If two white flowered plants are cross, what
percentage of their offspring will be white flowered?
15. Two short-haired guinea pigs are mated several
times. Out of 100 offspring, 25 of them have long
hair.
What are the probable genotypes of the
parents?
________ x ________
Show the cross to support your answer
10. A white flowered plant is crossed with a plant that is
heterozygous for the trait. What percentage of the
offspring will have purple flowers?
Mrs. Loyd 
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Review/Practice Packet Mendelian (Prob. Set I)
GG = gray hair
Gg = gray hair
gg = white hair
1.
BB = black eyes
Bb = black eyes
bb = red eyes
What are the phenotypes (descriptions) of rabbits that have the following genotypes:
Ggbb ____________________ ggBB ________________________
ggbb ____________________ GgBb _________________________
2.
A male rabbit with the genotype GGbb is crossed with a female rabbit with the genotype ggBb The square is set up below.
Fill it out and determine the phenotypes and proportions in the offspring.
How many out of 16 have grey fur and black eyes? ____
How many out of 16 have grey fur and red eyes? _____
How many out of 16 have white fur and black eyes? ____
How many out of 16 have white fur and red eyes? _____
3. A male rabbit with the genotype GgBb is crossed with a female
rabbit with the genotype GgBb The square is set up below. Fill it out
and determine the phenotypes and proportions in the offspring.
How many out of 16 have grey fur and black eyes? ____
How many out of 16 have grey fur and red eyes? _____
How many out of 16 have white fur and black eyes? ____
How many out of 16 have white fur and red eyes? _____
4. Show the cross between a ggBb and a GGBb. You'll have to set
the square up yourself!
Mrs. Loyd 
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Genetics
Review/Practice Packet Mendelian (Prob. Set I)
How to set up dihybrid crosses
A)
Figure out the genotypes of both traits for both parents.
B) Write out the parents’ genotypes together
C) Use the
F
i
r
s
t
O
u
t
s
i
d
e
I
n
s
i
d
e
L
a
s
t
ex. AABB X aabb
method to set up the test cross
1) Draw the arrows for each parent for the FOIL method. An example is given
below.
Parent 1
Parent 2
A
2) Set up the
cross for both sides.
A
B
B
X
a
a
b
b
Parent 1
AB
Parent 2
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Review/Practice Packet Mendelian (Prob. Set I)
3) Practice filling in the probable offspring below.
AB
AB
AB
ab
AB
AaBb
ab
ab
ab
4) To figure the phenotypic ratio, count the number of individuals with either the dominant or
recesssive phenotype for both traits! Then that ratio would be something like
4:4:4:4
or
9:3:3:1
PTC-taster- TT, Tt
Non-PTC taster – tt
Hitchhikers thumb- HH, Hh
Straight thumb – hh
Hair on mid-digit – MM, Mm
No hair on mid-digit- mm
Attached earlobes- EE, Ee
Free earlobes – ee
Straight pinky- PP, Pp
Bent pinky- pp
Widow’s peak- WW, Ww
No widow’s peak- ww
Dihybrid Crosses. Set up the crosses using the rules and the letters from the
other page.
1.
Can roll tongue- RR, Rr
Can’t roll tongue - rr
Now practice!
If a woman who is a non-PTC taster (recessive) with heterozygous hitchhikers thumb has children with a man who is a
heterozygous PTC taster with straight thumbs (recessive), what is the probability of them having each of the following
types of children? (Fill in the Punnett Square and the blanks).
Parents’ genotypes ____________ X ____________
a.
How many PTC taster, Hitchhikers thumb?
b.
How many PTC taster, straight thumb?
c.
How many Non-PTC taster, Hitchhikers thumb
d.
How many Non- PTC taster, straight thumb
e.
What is the phenotypic ratio?
Mrs. Loyd 
cschmittloyd@waukeeschools.org
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Review/Practice Packet Mendelian (Prob. Set I)
2.
If a woman who has no hair on her mid-digit (recessive)and is homozygous attached earlobes (dominant) has children
with a man who has hair on his mid-digit and has attached earlobes (heterozygous for both traits), what is the probability
of them having each of the following types of children? (Fill in the Punnett Square and the blanks).
Parents’ genotypes ____________ X ____________
3.
a.
How many hair, attached earlobes
b.
How many hair, not attached earlobes
c.
How many hairless, attached earlobes
d.
How many hairless, not attached earlobes
e.
What is the phenotypic ratio?
John Doe and Jane Doe want to have children and are thinking about how their childrens’ hands might look. What
would their children look like if they are both heterozygous for straight pinky and hitchhikers thumb? (Fill in the
Punnett Square and the blanks).
Parents’ genotypes ____________ X ____________
4.
a.
Straight pinky, hitchhikers thumb
b.
Straight pinky, Straight thumbs
c.
bent pinky, hitchhikers thumb
d.
bent pinky, Straight thumbs
e.
What is the phenotypic ratio?
Dohn Joe and Dane Joe want to have children and are thinking about how their childrens’ hair line and tongues will turn
out. They are both circus performers and want their children to follow in their footsteps. Their circus only accepts
people with a Widow’s Peak and who can roll their tongues. What would their children look like if Dohn is
heterozygous for both Widow’s peak and tongue rolling, and Dane is homozygous dominant for Widow’s peak and
heterozygous for tongue rolling? (Fill in the Punnett Square and the blanks).
Parents’ genotypes ____________ X ____________
a.
Widow’s Peak, Tongue Roller
b.
Widow’s Peak, non tongue roller
c.
Straight hair line, Tongue Roller
d.
Straight hair line, non tongue roller
e.
What is the phenotypic ratio?
f.
What are the chances of their child being able to join the circus?
Mrs. Loyd 
cschmittloyd@waukeeschools.org
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Review/Practice Packet Mendelian (Prob. Set I)
This problem will involve both a test cross and a Dihybrid Punnett Square
Background information:
You are a pigeon breeder. In order to make the most money as a pigeon breeder, you must sell mainly checkered winged, red
feather pigeons. Lucky for you checkered wings and red feathers are dominant in pigeons (plain wings and brown feathers
are recessive). To breed as many checkered winged, red feather pigeons as possible, you need to breed homozygous
checkered winged, red feather pigeons with each other (because all of the offspring would be checkered winged, red feather
pigeons). You know you have a female homozygous checkered winged, red feathered pigeon (you bred her yourself!) She is
so beautiful that she has won prizes in several pigeon beauty contests.
The Problem: You recently purchased a male pigeon that has checkered wings and red feathers from a shady pigeon dealer,
who claimed it was homozygous. Before you breed this male with your prize winning female, you want to be sure that it is
homozygous for both traits. Describe how you will be able to tell what the genotype for both traits of your pigeon in 1
generation. (test cross here) 5 points
a.
Illustrate the probable outcomes if your pigeon IS homozygous for both traits. (using a Punnett Square)
Mrs. Loyd 
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Genetics
Review/Practice Packet Non-Mendelian I (Prob. Set 2)
Most genetic traits have a stronger, dominant allele and a weaker, recessive allele. In an individual with a heterozygous
genotype, the dominant allele shows up in the offspring and the recessive allele gets covered up and doesn’t show; we call
this complete dominance. However, some alleles don’t completely dominate others. In fact, some heterozygous genotypes
allow both alleles to partially show by blending together how they are expressed; this is called incomplete dominance.
Other heterozygous genotypes allow both alleles to be completely expressed at the same time like spots or stripes; this is
called codominance. Examples of each are listed below.
Write what each type would be if they were heterozygous.
1.
Complete dominance = If a Red (RR) and White flower (rr) were crossbred, resulting in 100% Rr, what phenotype
would been seen according to the rules of COMPLETE dominance?
2.
Incomplete dominance = If a Red (RR) and White flower (rr) were crossbred, resulting in 100% Rr, what phenotype(s)
would been seen according to the rules of IN-complete dominance?
3.
Codominance = If a Red (RR) and White flower (WW) were crossbred, resulting in 100% RW, what phenotype(s) would
been seen according to the rules of CO-dominance?
Incomplete dominance practice Problems
4-6. Snapdragons are incompletely dominant for color; they have phenotypes red, pink, or white. The red flowers are
homozygous dominant, the white flowers are homozygous recessive, and the pink flowers are heterozygous. Give the
genotypes for each of the phenotypes, using the letters
“R” and “ r ” for alleles:
a. Red snapdragon
genotype: ______
b. Pink snapdragon
genotype: ______
c. White snapdragon
genotype: ______
Show genetic crosses between the following snapdragon parents, using the Punnett squares provided, and record the
genotypic and phenotypic %s below:
a. pink x pink
b. red x white
c. pink x white
Genotypic
Genotypic
Genotypic
%: ________________ %: ________________
%: ________________
Phenotypic
Phenotypic
Phenotypic
%: ________________ %: ________________
%: ________________
Mrs. Loyd 
cschmittloyd@waukeeschools.org
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Review/Practice Packet Non-Mendelian I (Prob. Set 2)
7-9. In horses, some of the genes for hair color are incompletely dominant. Genotypes are as follows: brown horses are BB,
white horses are bb and a Bb genotype creates a yellow-tannish colored horse with a white mane and tail, which is called
“palomino”. Show the genetic crosses between the following horses and record the genotypic and phenotypic percentages:
a. brown x white
Genotypic
%: ________________
Phenotypic
%: ________________
b. brown x palomino
c. palomino x palomino
Genotypic
%: ________________
Phenotypic
%: ________________
Genotypic
%: ________________
Phenotypic
%: ________________
10. Can palominos be considered a purebred line of horses? Why or why not?
11. Which two colors of horse would you want to breed if you wanted to produce the maximum
in the shortest amount of time?
numbers of palominos
12. In Smileys, eye shape can be starred (SS), circular (CC), or a circle with a star (CS). Write the genotypes for the pictured
phenotypes
_________
__________
___________
13. Show the cross between a star-eyed and a circle eyed.
What are the phenotypes of the offspring? ____________
What are the genotypes? __________
14. Show the cross between a circle-star eyed, and a circle eyed.
How many of the offspring are circle-eyed? ____________
How many of the offspring are circle-star eyed? ____________
15. Show the cross between two circle-star eyed.
How many of the offspring are circle-eyed? ____________
How many of the offspring are circle-star eyed? ____________
How many are star eyed? ___________
Mrs. Loyd 
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Review/Practice Packet Non-Mendelian I (Prob. Set 2)
Name ____________________________________
Practice: Codominance and Incomplete Dominance
Figure out which of the combinations represent codominant traits and which are incomplete. Remember that the "medium"
trait must always be heterozygous. Put “Co” or “I” next to each letter.
a)
Birds can be blue, white, or white
with blue-tipped feathers.
b)
Flowers can be white, pink, or red.
c)
A Hoo can have curly hair, spiked
hair, or a mix of both curly and
spiked.
d)
A Sneech can be tall, medium, or
short.
e)
A Bleexo can be spotted, black, or
white.
Mrs. Loyd 
cschmittloyd@waukeeschools.org
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Review/Practice Packet Non-Mendelian I (Prob. Set 2)
All chickens have combs on their heads, but it does not always look the same. The comb is a fleshy growth on the
top of the chicken's head. Both male and female chickens have combs, but the ones on the male are larger.
Combs of different breeds may look different in shape and even in color.
1. On the cross pictured below, what must be the genotypes of the two parents for the outcome to always be a
walnut offspring?
____________ x _____________
2. Show a Punnett square for the following cross and describe the
phenotypic ratios.
RrPp x RrPp
Show a Punnett square for the following cross and
describe the phenotypic ratios.
4. Single comb x Walnut (RrPp)
6. A rose crossed with a pea produces six
walnut and five rose offspring. What
must be the genotypes of the parents?
Show the cross.
Show a Punnett square for the following cross and
describe the phenotypic ratios.
5. Single comb x Pea comb (rrPp)
Mrs. Loyd 
cschmittloyd@waukeeschools.org
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Review/Practice Packet Non-Mendelian I (Prob. Set 2)
Codominance Worksheet (Blood types)
Human blood types are determined by genes that follow the CODOMINANCE pattern of inheritance.
There are two dominant alleles (A & B) and one recessive allele (O).
Blood Type
(Phenotype)
Genotype
Can donate blood
to:
Can receive
blood from:
O
ii (OO)
A,B,AB and O
(universal donor)
O
AB
IAIB
AB
A,B,AB and O
(universal
receiver)
A
IAIA or
IAi (IAO)
AB, A
O,A
B
IBIB or
I i (IBO)
AB,B
O,B
B
1. Write the genotype for each person based on the description:
a. Homozygous for the “B” allele
b. Heterozygous for the “A” allele
c. Type O
d. Type “A” and had a type “O” parent
e. Type “AB”
f. Blood can be donated to anybody
g. Can only get blood from a type “O” donor
_________
_________
_________
_________
_________
_________
_________
2.
Pretend that Brad Pitt is homozygous for the type B allele, and
Angelina Jolie is type “O.”
What are all the possible blood types of their baby? (Do the punnett square)
_________________________________________________________________
3.
Complete the punnett square showing all the possible blood types for the offspring
produced
by a type “O” mother and an a Type “AB” father. What are percentages of each
offspring?
_________________________________________________________________
4.
Mrs. Essy is type “A” and Mr. Essy is type “O.” They have three children named
Matthew, Mark, and Luke. Mark is type “O,” Matthew is type “A,” and Luke is type
“AB.” Based on this information:
a. Mr. Essy must have the genotype ______
b. Mrs. Essy must have the genotype ______ because ___________ has blood
type ______
c. Luke cannot be the child of these parents because neither parent has the allele _________
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Review/Practice Packet Non-Mendelian I (Prob. Set 2)
5.
Two parents think their baby was switched at the hospital. Its 1968, so DNA fingerprinting technology
does not exist yet. The mother has blood type “O,” the father has blood type “AB,”
and the baby has blood type “B.”
a. Mother’s genotype: _______
b. Father’s genotype: _______
c. Baby’s genotype: ______ or ________
d. Punnett square showing all possible genotypes for children produced by this
couple.
e. Was the baby switched? _______________________
6.
Two other parents think their baby was switched at the hospital. Amy the mother has blood type “A,”
Linville the father has blood type “B,” and Priscilla the baby has blood type “AB.”
7.
a.
Mother’s genotype: _______ or ________
b.
Father’s genotype: _______ or ________
c.
Baby’s genotype: ______
d.
Punnett square that shows the baby’s genotype as a possibility
e.
Could the baby actually be theirs? _________________________
Based on the information in this table, which
men could not be the father of the baby?
(hint… look at the baby’s blood type
only…)______________________________
You can use the Punnett square if you
need help figuring it out.
8.
The sister of the mom above also had issues
with finding out who the father of her baby
was. She had the state take a blood test of
potential fathers. Based on the information
in this table, why was the baby taken away
by the state after the test? (hint… look at
the baby’s blood type
only…)______________________________
____________________________________
Name
Blood Type
Name
Blood Type
Mother
Type A
Mother
Type O
Baby
Type B
Baby
Type AB
The mailman
Type O
Bartender
Type O
The butcher
Type AB
Guy at the club
Type AB
The waiter
Type A
Cabdriver
Type A
The cable guy
Type B
Flight attendant
Type B
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Review/Practice Packet Non-Mendelian I (Prob. Set 2)
BLOOD TYPE & INHERITANCE
In blood typing, the gene for type A and the gene for type B are codominant. The gene for type
O is recessive. Using Punnett squares, determine the possible blood types of the offspring
when:
1. Father is type O, Mother is type O
__________%
__________%
__________%
__________%
O
A
B
AB
2. Father is type A, homozygous; Mother is type B, homozygous
__________%
__________%
__________%
__________%
O
A
B
AB
7. Father is type A, heterozygous; Mother is type B, heterozygous
__________%
__________%
__________%
__________%
O
A
B
AB
8. Father is type O, Mother is type AB
__________%
__________%
__________%
__________%
O
A
B
AB
9. Father and Mother are both type AB
__________%
__________%
__________%
__________%
Page 14 of 20
O
A
B
AB
4/10/15
Review/Practice Packet Non-Mendelian II (Prob. Set 3)
Genetics: X Linked Genes
In fruit flies, eye color is a sex linked trait. Red is dominant to white.
1. What are the sexes and eye colors of flies with the following genotypes:
X R X r _________________
X R X R _________________
X R Y _________________
X r Y _________________
2. What are the genotypes of these flies:
white eyed, male ____________
white eyed, female ___________
red eyed female (heterozygous) ________
red eyed, male ___________
3. Show the cross of a white eyed female X r X r with a red-eyed male X R Y .
4. Show a cross between a pure red eyed female and a white eyed male.
What are the genotypes of the parents:
___________ X _______________
How many are:
white eyed, male___
white eyed, female ___
red eyed, male ____
red eyed, female ____
5. Show the cross of a red eyed female (heterozygous) and a red eyed male. What are the genotypes of the
parents?
___________ X ________________
How many are:
white eyed, male___
white eyed, female ___
red eyed, male ____
red eyed, female ____
Math: What if in the above cross, 100 males
were produced and 200 females. (think about the
percentage of the total #)
6. How many total red-eyed flies would there be?
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Review/Practice Packet Non-Mendelian II (Prob. Set 3)
7. In humans, hemophilia is a sex linked trait. Females can be normal, carriers, or have the disease. Males
will either have the disease or not (but they won’t ever be carriers)
= female, normal
= male, normal
= female, carrier
= male, hemophiliac
= female, hemophiliac
Show the cross of a man who has hemophilia with a woman who is a carrier.
8. What is the probability that their children will have the disease? __________
9. A woman who is a carrier marries a normal man. Show the cross. What is the probability
that their children will have hemophilia? What sex will a child in the family with hemophilia
be?
10. A woman who has hemophilia marries a normal man. How many of their children will have
hemophilia, and what is their sex?
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Review/Practice Packet Non-Mendelian II (Prob. Set 3)
Pedigree Worksheet Use the given pedigrees to answer the
following questions:
The pedigree to the right
shows the passing on of
straight thumbs (recessive)
and Hitchhiker’s Thumb
(dominant) in a family.
Shaded shapes mean the
person has a straight thumb
I
1
II
2
1
3
2
1
III
IV
4
2
1
2
3
4
3
1. What is the genotype of IV-1?
5. What is the genotype II-3?
2. What is the genotype IV-3?
6. Is it possible for individual IV-2 to be a
carrier?
3. What is the genotype of III-1?
4. What is the genotype III-2?
8. The pedigree to the right shows the passing
on of colorblindness (a recessive, sexlinked trait). Fill in the numbers for each
generation (generation IV is done for you).
9. What do the half shaded circles mean?
7. Why/Why not?
I
III
I
10. What is the ONLY gender that carriers of
colorblindness can be?
9. Which individuals are colorblind?
____________________________________
10. What is the genotype of person II-2?
11. What is the genotype of person I-1?
III
IV
1
2
3
4
5
6
7
8
12. What is the genotype of person III-3?
13. If person IV-1 marries a female who is not colorblind and is not a carrier, what are the chances of their
male offspring being colorblind?
14. What about their female offspring?
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Review/Practice Packet Non-Mendelian II (Prob. Set 3)
= Sickle Cell
Anemia
I
1
2
4
5
II
1
III
1
2
2
3
3
4
6
7
8
5
NOTE- carriers are not shown on this pedigree although Sickle Cell Anemia IS A
RECESSIVE DISORDER.
11.
Which members of the family above are afflicted with sickle cell anemia?
12.
How are individuals III-4 and III-5 related?
13.
How are individuals I-1 and I-2 related?
14.
How are individuals II-7 and III-2 related?
15.
How are individuals I-2 and III-5 related?
16.
How many children did individuals I-1 and I-2 have?
17.
How many girls did II-1 and II-2 have? ___________ How many have sickle cell anemia?
18.
Label the possible genotypes for all individuals in the pedigree. One person can have more than one
possible genotype
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BIOLOGY Problem Set with Probability Calculations
Solve the following genetics problems. Show your work as clearly and completely as possible. Hint: when
the problem gives you genetic information, get it written down.
1. During a recent hunting season, a male and
female otter were captured and mated. Both
otters were of the southern species, so they were
dark brown in color. Once the offspring were
born, the owners noticed quite a few little creamcolored otters running around, as well as a large
number of little dark brown otters. If both parents
were heterozygotes and there were 48 little
brown otters, how many little cream-colored
otters were there? Show your Punnett square
work.
2. For this question, use your imagination. A
pink elephant and a green elephant were mated
and only pink baby elephants were born of the
union. It two of these offspring were mated and
eventually produced a total of 64 baby elephants,
how many of these should be pink and how many
should be green? Show your Punnett square
work.
3. Brown color in mice is dominant over albinism.
In a given cross between a brown mouse and an
albino mouse, six of the offspring were brown
and five were albinos. What was the genotype of
the original brown parent? Show your punnett
square work.
4. Starchy grain is dominant over sugary grain in
corn. If, in a cross between these two types, 58
of the offspring were sugary, how many would be
starchy? Show your Punnett square work.
5. A certain white-fruited squash; when selffertilized, produced both white and yellow-fruited
squash offspring. If 21 of the offspring were
yellow, how many white squash would be
expected? Show your Punnett square work.
6. Short hair is dominant over long hair in guinea
pigs. A short-haired guinea pig, one of whose
parents was a long-haired animal, was mated
with a long-haired guinea pig. If, blindfolded, you
selected one of their litter from the cage, what is
the chance you would get a long-haired animal?
7. If an animal with the genotype Cc produces
100 eggs, how many of these eggs should have
the genetic formula C? How many probably have
the formula c? How many have the formula Cc?
Why?
8. Applying the rules relating to the choice of
symbols for genes, make a number of matings
between trotting horses, Tt and Tt, and obtain 24
foals. How many of these foals would be
pacers? Use a Punnett square to explain why.
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BIOLOGY Problem Set with Probability Calculations
9. If two parents, who have the same visible
characteristics, produce some offspring
that are like the parents, and some
different, write the formulas of the parents
using any symbols you choose. Show
the Punnett square.
_______ x _______
10. In eye color, the darker colors are
usually dominant over lighter ones. A
brown-eyed boy whose mother had
blue eyes married a brown-eyed girl
whose father had blue eyes. What is
the chance that their first-born child
will be blue-eyed? Show your work.
11. Two brown minks mated and
produced brown and silver-blu babies.
What were the genotypes of the
parents? Show your Punnett square
work.
_______ x _______
12. Melanoma is a cancer of the skin. A
normal woman (without melanoma)
married a man with melanoma. They
had two children, A and B. The man
then had an operation and the
melanoma was successfully removed.
They then had two additional children,
C and D. What would be the
phenotypes of children A, B, C, and
D? Explain.
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