Multiple Choice
Identify the letter of the choice that
best completes the statement or answers the question.
A
B
C
D
1.
Which
of the following are shown in a karyotype?
a.
homologous chromosomes
b.
sex chromosomes
c.
autosomes
d.
all of the above
A
B
C
D
2.
In
humans, a male has
a.
one X chromosome only.
b.
two X chromosomes.
c.
one X chromosome and one Y
chromosome.
d.
two Y
chromosomes.
A
B
C
D
3.
What
is the ultimate source of genetic variability?
a.
inbreeding
b.
radiation
c.
hybridization
d.
mutations
A
B
C
D
4.
Which
of the following can be observed in a karyotype?
a.
a change in a DNA base
b.
an extra chromosome
c.
genes
d.
alleles
A
B
C
D
5.
Genetic engineering involves
a.
reading a DNA sequence.
b.
editing a DNA sequence.
c.
reinserting DNA into living
organisms.
d.
all of the
above
A
B
C
D
6.
Sickle
cell disease is caused by a
a.
small change in the DNA of a single
gene.
b.
change in the
size of a chromosome.
c.
change in two genes.
d.
change in the number of chromosomes in a
cell.
A
B
C
D
7.
Which
of the following statements is true?
a.
Females cannot have hemophilia.
b.
The father of a colorblind boy may be
colorblind.
c.
A sex-linked
allele cannot be dominant.
d.
The mother of a colorblind boy must be
colorblind.
A
B
C
D
8.
The
process of DNA fingerprinting is based on the fact that
a.
the most important genes are different among most
people.
b.
no two people,
except identical twins, have exactly the same DNA.
c.
most genes are dominant.
d.
most people have DNA that contains
repeats.
A
B
C
D
9.
Selective breeding produces
a.
more offspring.
b.
fewer offspring.
c.
desired traits in offspring.
d.
transgenic organisms.
A
B
C
D
10.
The
purpose of gene therapy is to
a.
cure genetic disorders.
b.
determine the sequences of
genes.
c.
remove mutations
from genes.
d.
change dominant
alleles to recessive alleles.
A
B
C
D
11.
Because the allele that causes a form of leukemia and the allele that causes
neurofibromatosis are located on chromosome 22, they
a.
are dominant.
b.
are never separated by
recombination.
c.
are
linked.
d.
contain
repetitive DNA.
A
B
C
D
12.
What
is the approximate probability that a human offspring will be female?
A
B
C
D
13.
The
failure of chromosomes to separate during meiosis is called
a.
nondisjunction.
b.
X-chromosome inactivation.
c.
Turner’s syndrome.
d.
Down syndrome.
A
B
C
D
14.
Which
of the following is determined by multiple alleles?
a.
Rh blood group
b.
ABO blood group
c.
PKU
d.
Huntington’s disease
A
B
C
D
15.
Which
of the following have been produced by selective breeding?
a.
horse breeds
b.
cat breeds
c.
dog breeds
d.
all of the above
A
B
C
D
16.
What
is the probability that a human sperm cell will carry an X chromosome?
A
B
C
D
17.
Which
of the following is most likely to bring together two recessive alleles for a genetic
defect?
a.
inbreeding
b.
hybridization
c.
genetic engineering
d.
transformation
A
B
C
D
18.
Sex-linked genes are located on
a.
the autosomes.
b.
the X chromosome only.
c.
the Y chromosome only.
d.
both the X chromosome and Y
chromosome.
A
B
C
D
19.
How
many chromosomes are shown in a normal human karyotype?
A
B
C
D
20.
Why is
Dolly a clone?
a.
The source of her
DNA was a single body cell.
b.
The DNA molecules in all her cells are
identical.
c.
She was produced
using the DNA from an adult’s egg cell.
d.
She is genetically identical to her
offspring.
A
B
C
D
21.
The
Human Genome Project is an attempt to
a.
make a DNA fingerprint of every person’s
DNA.
b.
sequence all
human DNA.
c.
cure human
diseases.
d.
identify alleles
in human DNA that are recessive.
A
B
C
D
22.
Colorblindness is more common in males than in females because
a.
fathers pass the allele for colorblindness to their sons
only.
b.
the allele for
colorblindness is located on the Y chromosome.
c.
the allele for colorblindness is recessive and located on
the X chromosome.
d.
males who are colorblind have two copies of the allele for
colorblindness.
A
B
C
D
23.
A cat
that has only orange spots
a.
has no Barr bodies.
b.
must be a male.
c.
must be a female.
d.
may be a male or a female.
A
B
C
D
24.
What
has been an advantage of producing transgenic plants?
a.
increasing the food supply
b.
using more pesticides
c.
producing clones
d.
studying human genes
A
B
C
D
25.
Human
females produce egg cells that have
a.
one X chromosome.
b.
two X chromosomes.
c.
one X or one Y chromosome.
d.
one X and one Y chromosome.
