Download D. 100% dominant

Genetics Exam
Biology
Directions:
(WORK genetics problems out on scratch paper
before you mark you answer on the Scantron Sheet.)
There are 25 questions. Each question is worth 4 points.
There are 100 points possible
Choose the best correct answer.
Completely fill in the correct “box” on your scantron with
your choice with a # 2 pencil.
Completely erase any changes or stray marks from the
scantron answer sheet, or the scantron machine may
count the partially erased change or stray mark as an
incorrect response.
THIS EXAM IS OPEN NOTEBOOK.
Raise your hand if you have any questions.
When you are finished, bring these Exam questions and
your scantron answer sheet to the Instructor.
GENETICS Exam-Biology:
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═══════════════════════════════════════════════
For Questions 1 - 4 match the cross with the results in the key:
KEY:
A.
B.
C.
D.
3:1
1:2:1
1:1
100% dominant
1.
2.
3.
4.
The phenotype of a monohybrid cross of homozygous dominant to homozygous recessive
The genotype of a monohybrid cross of heterozygous to heterozygous
The phenotype of a monohybrid cross of heterozygous to heterozygous
The phenotype of a monohybrid cross of heterozygous to homozygous recessive
═══════════════════════════════════════════════
5.
In rabbits, if B = dominant Black allele and b = recessive white allele, which of these genotypes
could a white rabbit have?
A.
Bb
B.
BB
C.
bb
D.
all three answers, ( "A", "B", and "C") are correct
6.
A man of blood type A and a woman of blood type B produce a child of type O. If the couple
were to have many more children, what are the possible blood types possible in the offspring?
A.
type A
B.
type B
C.
type A, B, and AB
D.
type A, B, AB, and O
7.
A chicken having black feathers is crossed with a chicken having
white feathers and the result is chickens that appear to have blue feathers. What inheritance
pattern explains these results?
A.
homozygous dominant
B.
complete dominance
C.
sex-linked
D.
incomplete dominance
GENETICS Exam-Biology:
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8.
In problem # 7 above, if black feathers are represented by the allele "B", and white feathers are
represented by the allele "b", then what is the genotype of the offspring?
A.
blue
B.
bb
C.
BB
D.
Bb
9.
A woman is color blind. What are the chances of her daughters being color blind if she marries
a man with normal vision?
A.
1 out of 16
B.
zero
C.
1 out of 2, 50%
D.
1 out of 4, 25%
10.
An individual has a genetic disorder that only expresses itself if both alleles are recessive. In a
complete dominance situation, what would be the phenotype for a Heterozygous individual?
(This is NOT an X-linked problem)
A.
they would have the disorder
B.
they would not have the disorder, and would not be a carrier
C.
they would not have the disorder, and would be a carrier
D.
they would have the disorder, but be unable to pass it on to any offspring.
11.
In werewolves, L = long fangs, l = short fangs, and S = slobbery, drooling foam saliva, s =
drools just a bit saliva. A Long Fanged Slobbery male mated to a short fanged drools just a bit,
and produces an F1 of 16 Long Fanged Slobberys. Give all possible genotypes for all offspring.
A.
LlSs
B.
LlSs, Llss, llSS, llss, Llss, LLss, llSs
C.
Llss, llSs
D.
llss
12.
In the problem # 11 above, give the genotype of both parents. Specify which parent is male,
and which is female.
A.
Male: LLSS,
Female: llss
B.
Male: LlSs,
Female: llss
C.
Male: LlSs, LLSS, Female: llss
D.
Male: llss
Female: LlSs
GENETICS Exam-Biology:
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13.
In Bigfoots, really smelly feet (n) is sex linked recessive, non-smelling feet (N) is dominant.
Really smelly armpits (A) are dominant over partially smelly armpits (a). A male really smelly
feet, partially smelly armpit Bigfoot has a mother with what kind of possible genotype(s)?
A.
XnaXna
B.
XNAXna
C.
XnAXna
D.
XnaXnA
E.
All 4 answers above are possible, (A,B,C & D)
14.
The male offspring in problem # 13 above is mated to a very beautiful, really smelling feet,
partially smelly armpit Bigfoot female. What are the genotypes possible for the F1?
A.
XnaXna, XnaYna
B.
XnaXna
C.
XnaYa
D.
XnaXna, XnaYa
E.
XnaXNA, XnaYA
15.
In the tufted tit mouse, the length of the tail feathers may be long (LL), or really short (ll), or
kind of short (Ll). If kind of short is crossed with kind of short, then what proportion of the F1
will also be kind of short ?
A.
25%
B.
50%
C.
75%
D.
100%
16.
From the following blood types, determine which baby belongs to which parents:
(All the parents are monogamous and faithful)
Mrs. Lily Munster
Mr. Herman Munster
Type A
Type B
Baby 1 = Type O
A.
B.
C.
D.
E.
Baby 1 =
Baby 1 =
Baby 1 =
Baby 1 =
Baby 1 =
Mr. Brady
Mrs. Brady
Type A
Type AB
Baby 2 = Type B
The Munsters
The Bradys
The Munsters
The Bradys
The Munsters
Baby 2 =
Baby 2 =
Baby 2 =
Baby 2 =
Baby 2 =
The Bradys
The Munsters
The Munsters
The Bradys
The Bradys or The Munsters
GENETICS Exam-Biology:
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17.
Hemophilia is a sex-linked recessive human affliction. Hemophilia A is caused by the absence
or minimal presence of a particular clotting factor called factor VIII. Hemophilia is called the
bleeder's disease because the affected person's blood does not clot. Not only do hemophiliacs
bleed externally after an injury, they also suffer from internal bleeding, particularly around
joints. At the turn of the century, hemophilia was common in the royal families of Europe, and
all of the affected males could trace their ancestry to Queen Victoria of England. Because none
of the queen's ancestor or relatives were affected, it seems that the RECESSIVE allele she
carried arose by mutation either in Queen Victoria or one of her parents. Her daughters Alice
and Beatrice were carriers and introduced the allele into the ruling houses of Russia and Spain.
Alexis, the last heir to the Russian throne before the Russian Revolution, was a hemophiliac.
The current British royal family has no hemophiliacs because Victoria's eldest son, King
Edward VII, did not receive the allele and therefore could not pass it on to any of his
descendants.
A hemophiliac man reproduces with a homozygous normal woman. What are the chances that
their sons will be hemophiliacs?
A.
0%
B.
25%
C.
50%
D.
75%
E.
100%
18.
In Question Number 17 above, what is the chance that their daughters will be
hemophiliacs?
A.
0%
B.
25%
C.
50%
D.
75%
E.
100%
19.
In Question number 17 above, what is the chance that their daughters will be carriers (= they
carry the damaging allele, but their phenotype is normal)?
A.
0%
B.
25%
C.
50%
D.
75%
E.
100%
GENETICS Exam-Biology:
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20.
Muscular Dystrophy, as the name implies, is characterized by a wasting away of the muscles.
The most common form Duchenne muscular dystrophy, is an X-linked (sex-linked) recessive
disorder that occurs in about one in 5,000 live male births. Symptoms, such as waddling gait,
toe walking, frequent falls, and difficulty in rising may appear as soon as the child start to walk.
Muscle weakness intensifies until the individual is confined to a wheelchair. The condition
also affects the muscles that allow us to breathe and the heart; death usually occurs during the
teenage years, therefore, affect males are rarely fathers. The recessive allele remains in the
population by passage from carrier mother to carrier daughter.
A son with Duchenne muscular dystrophy is born to a couple who both appear to be normal.
What are the chances that any child born to this couple will have Duchenne muscular
dystrophy?
A.
0%
B.
25%
C.
50%
D.
75%
E.
100%
21.
a.
b.
c.
d.
22
a.
b.
c.
d.
Two similar chromosomes that you inherit from your parents (one from your mother, one from
your father) are called:
homologous chromosomes.
sister chromatids.
sex chromosomes.
homozygous alleles.
Which of the following phrases describes the Punnett square in Figure 6.1?
1/4 probability of heterozygous offspring
monohybrid heterozygous-heterozygous cross
3/4 probability of homozygous offspring
dihybrid heterozygous-heterozygous cross
GENETICS Exam-Biology:
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23.
a.
b.
c.
d.
24.
a.
b.
c.
d.
Which of the following statements is true of homozygous alleles?
They are always inherited together.
They are different forms of the same trait.
They are identical forms of the same gene.
They are not identical forms of the same gene.
The Punnett square in Figure 7.1 shows a cross between two parents who have the
genotype Ss for a genetic disorder caused by a recessive allele. Which of the following
will have the genetic disorder?
Ss parent
Ss offspring
SS offspring
ss offspring
__________________________________________________________________________________
In cats,
S = short hair, s = long hair,
Xc = yellow coat, XC = black coat,
XCXc = tortoiseshell (calico ) coat.
25.
If a long-haired, yellow male is crossed with a tortoiseshell female, homozygous for short hair,
what will be the expected phenotypic results?
A.
females - 1 long-haired tortoise shell : 1 long haired yellow
males - 1 long-haired black : 1 long haired yellow
B.
females - 1 short haired tortoise shell : 1 short haired yellow
males - 1 short haired yellow : 1 short haired black
C.
1 out of 16 short haired tortoise shell females, the rest male
D.
1:2:1
GENETICS Exam-Biology:
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