DNA Quiz 2

Name: 

Mendel’s Genetics

 

 

True/False
Indicate whether the sentence or statement is true or false.
1.
The law of segregation states that two or more pairs of alleles separate independently of one
another during gamete formation.
2.
Cells that contain a single set of chromosomes are said to be haploid (N).
3.
Crosses involving a study of one gene are called monohybrid crosses.
4.
A dominant allele masks the effect of a recessive allele.
5.
Mendel concluded that the patterns of inheritance are determined entirely by the environment.
6.
A Punnett square represents the phenotype of an organism.
7.
The physical appearance of an individual organism, as determined by the genes it has inherited from its parents, is called its genotype.
8.
Individuals must exhibit a trait in order for it to appear in their offspring.
9.
In codominance, two alleles are expressed at the same time.
 

Multiple Choice
Identify the letter of the choice that best completes the statement or answers the question.
10.
In fruit flies, the gene for long wings, L, is dominant to the gene for short wings, l.  A heterozygous long wing male and a short wing female produce many offspring. The possible genotype(s) among the long-winged offspring is (are)
a.
Ll only
c.
LL and Ll
b.
ll only
d.
Ll and ll.
11.
In drosophila, curled wing is recessive to straight wing. If a homozygous straight-winged fly is mated with a curled-wing fly, how many different phenotypes will be produced?
a.
1
c.
3
b.
2
d.
4
12.
If an organism has two identical alleles for a trait, it is
a.
homozygous.
c.
homozygous dominant.
b.
heterozygous.
d.
heterozygous recessive.
13.
Alleles for the same trait separate during
a.
fertilization.
c.
meiosis I.
b.
mitosis.
d.
meiosis II.
14.
The inheritance of genes that determine one trait (hair color) is not affected by the inheritance of genes that control another trait (tongue rolling).  Which of Mendel’s rules apply to the above statement?
a.
the rule of dominance
c.
the rule of independent assortment
b.
the rule of segregation
15.
In fruit flies, the gene for straight wings, C, is dominant to the gene for curly wings, c. Two flies, when bred, produced 98 straight-winged and 102 curly-winged offspring.  What was the genotype of the curly-winged offspring?
a.
CC
c.
cc
b.
Cc
d.
straight-winged
16.
All homozygous individuals have:
a.
the same genotype
c.
two alleles exactly alike
b.
the same phenotype
d.
a hybrid genotype.
17.
If a family has three daughters, the probability that the next child will be a girl is
a.
1/4.
c.
1/2.
b.
1/3.
d.
3/4.
18.
Mendel explained the reappearance of recessive traits in the F2 generation in his principle of
a.
independent assortment.
c.
dominance.
b.
segregation.
d.
blending inheritance.
19.
If any offspring from a test cross show a recessive phenotype, the parent with the unknown genotype is
a.
heterozygous dominant.
c.
heterozygous recessive.
b.
homozygous dominant.
d.
homozygous recessive.
20.
A homozygous black rabbit is mated with a heterozygous rabbit. If black is dominant over white, they should produce:
a.
all white rabbits
b.
all black rabbits
c.
half black and half white rabbits
d.
one pure dominant and heterozygous individual.
21.
Mendel’s finding that the inheritance of one trait had no effect on the inheritance of another became known as the
a.
law of dominance.
c.
law of segregation.
b.
law of universal inheritance.
d.
law of independent assortment.
22.
The phenotype of an organism
a.
represents its genetic composition.
b.
reflects all the traits that are actually expressed.
c.
occurs only in dominant pure organisms.
d.
cannot be seen.
23.
In humans the ability to taste PTC paper is dominant to non-tasting and hair color shows incomplete dominance (Dark hair x blond hair => brown hair).  A brown haired man who cannot taste PTC paper marries a woman with brown hair and who can taste PTC paper.  Their first child had brown hair and could not taste PTC paper. What are the chances that their next child will be a brown taster?
a.
1/4
c.
1/8
b.
1/2
d.
3/8
24.
Two long-furred cats were mated and produced 25 percent short-furred cats.  The parents were probably:
a.
pure recessive individuals
b.
pure dominant individuals
c.
heterozygous individuals
d.
one pure dominant and heterozygous individual.
25.
When certain types of black roosters are crossed with white hens, speckled chickens result. These chickens, which have a mixture of black and white feathers, show
a.
dominance.
c.
polygenes.
b.
codominance.
d.
recessive
26.
codominance : both traits are displayed::
a.
probability : crosses
c.
homozygous : alleles are same
b.
heterozygous : alleles are the same
d.
Punnett square : chromosomes combine
27.
A Punnett square is used to determine the
a.
probable outcome of a cross.
c.
result of segregation.
b.
actual outcome of a cross.
d.
result of meiosis I.
28.
If a family has four sons, the probability that the next child will be a boy is
a.
1/2.
c.
1/5.
b.
1/4.
d.
4/5.
29.
Suppose that on Mars green creatures are dominant over red creatures and that 3-eyes are recessive to 4-eyes.  Assume that inheritance of traits on Mars occurs the same way as on Earth.  A cross between 2 GgEe Martians would result in what fraction of the offspring being red-3-eyed Martians?
a.
1/16
c.
4/16
b.
2/16
d.
9/16
30.
The fact that a man and woman, both of whom have wavy hair, could have children with curly hair, wavy hair, or straight hair is best explained by the phenomenon called
a.
codominance.
b.
dominance.
c.
incomplete dominance.
d.
None of the above; this would be impossible.
31.
A Punnett square does not show the
a.
genetic makeup of the eggs.
c.
genetic makeup of the sperm.
b.
probable outcome of a cross.
d.
actual outcome of a cross.
32.
The “father” of genetics was
a.
T. A. Knight.
c.
Gregor Mendel.
b.
Dr. Judd.
d.
None of the above
33.
What is the probability that the offspring of a homozygous dominant individual and a  homozygous recessive individual will exhibit the dominant phenotype?
a.
0.25
c.
0.66
b.
0.5
d.
1.0
34.
Which of the following is the designation for Mendel’s original pure strains of plants?
a.
P
c.
F1
b.
P1
d.
F2
35.
F2 : F1 ::
a.
P : F1
c.
F1 : P
b.
F1 : F2
d.
dominant trait : recessive trait
36.
The passing of traits from parents to offspring is called
a.
genetics.
c.
development.
b.
heredity.
d.
maturation.
37.
homozygous : heterozygous ::
a.
heterozygous : Bb
c.
dominant : recessive
b.
probability : predicting chances
d.
homozygous : BB
38.
The phenotype of an organism
a.
represents its genetic composition.
b.
reflects all the traits that are actually expressed.
c.
occurs only in dominant pure organisms.
d.
cannot be seen.
39.
If an individual has two recessive alleles for the same trait, the individual is said to be
a.
homozygous for the trait.
c.
heterozygous for the trait.
b.
haploid for the trait.
d.
mutated.
40.
Tallness (T) is dominant to shortness (t) in pea plants. Which of the following represents a genotype of a pea plant that is heterozygous for tallness?
a.
T
c.
Tt
b.
TT
d.
tt
41.
How many different phenotypes can be produced by a pair of codominant alleles?
a.
1
c.
3
b.
2
d.
4
chp_9_web_tutorial_files/i0440000.jpg
42.
Refer to the illustration above. The genotype represented by the cell labeled “2” is
a.
GgIi.
c.
GI.
b.
GGIi.
d.
Gi.
In rabbits, black fur (B) is dominant to brown fur (b). Consider the following cross between two rabbits.
      chp_9_web_tutorial_files/i0460000.jpg
43.
Refer to the illustration above. Both of the parents in the cross are
a.
black.
c.
homozygous dominant.
b.
brown.
d.
homozygous recessive.
44.
Refer to the illustration above. The genotypic ratio of the F1 generation would be
a.
1:1.
c.
1:3.
b.
3:1.
d.
1:2:1.
45.
In pea plants, yellow seeds are dominant over green seeds. What would be the expected genotype ratio in a cross between a plant with green seeds and a plant that is heterozygous for seed color?
a.
1:3
c.
4:1
b.
1:2:1
d.
1:1

 

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