Download when a woman is color blind ______.

Color blindness is rare in women but
possible; when a woman is color blind
________.
20%
1.
20%
20%
3
4
20%
her father will also be color
blind
all of her sons will also be
color blind
her mother will also be color
blind
she will also suffer from
Turner's syndrome
her genotype will be XXY
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
The probability that a crossover will disrupt
the linkage between two genes is
proportional to the ________.
20%
1.
20%
20%
3
4
20%
number of alleles for the
genes
distance between the genes
diploid number for that
species
time of expression of the
genes
degree of pleiotropy
displayed by the gene
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
The incidence of Down
syndrome increases ________.
20%
1.
20%
20%
3
4
20%
when identical twins or
triplets have been conceived
both parents are
heterozygous for Down
syndrome
if either of the parents is
aneuploid
for families with Down
syndrome in their pedigree
once the mother's age is
greater than 35
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
Normal human cells have 46 chromosomes;
a monosomic cell will have ________
chromosome(s).
20%
1.
2.
3.
4.
5.
1
20%
20%
20%
3
4
20%
1
22
23
45
92
2
3
4
5
1
2
5
Cri-du-chat syndrome is caused by a
deletion on chromosome 5; deletions occur
when ________.
20%
1.
20%
20%
3
4
20%
a portion of a chromosome is
relocated onto a second
chromosome
homologous chromosomes fail
to separate during meiosis
a portion from the end or within
the middle is lost
a son inherits a defective X
chromosome from his mother
a section of chromosome breaks
free but is reconnected to its
chromosome in reverse order
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
Sickle-cell trait occurs in individuals heterozygous for the
autosomal-recessive gene. What is the likelihood that a
person who has two parents with sickle-cell trait will have
the disorder?
20%
1.
2.
3.
4.
5.
1
20%
20%
20%
3
4
20%
100% (certain)
0% (impossible)
50%
25%
not enough
information given to
answer the question
2
3
4
5
1
2
5
Genetic abnormalities can be diagnosed
prenatally through ________.
20%
20%
20%
20%
3
4
20%
1. chorionic villi
sampling
2. fetoscopy
3. amniocentesis
4. an examination of
fetal blood
5. all of the choices
1
2
3
4
5
1
2
5
Neurobiological disorders (NBDs)
such as schizophrenia ________.
20%
1.
20%
20%
3
4
20%
must be autosomal recessive since
afflicted parents always have
afflicted children
are clearly caused by genetic factors
since both identical twins always
either suffer the disease or do not
may have genetic susceptibilities but
do not appear to be caused by a
single gene.
appear to be caused by an
autosomal-dominant gene
appear to have some sex linkage
since men suffer NBDs more often
than women
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
When X-chromosome nondisjunction occurs
during mitosis in an embryo, the ________.
20%
1.
20%
20%
3
4
20%
affected gamete results in
aneuploidy after conception
percentage of affected sons will
be greater than affected
daughters
individual will be genetically
male but phenotypically female
incidence of X-linked disorders
will no longer show a gender
bias
daughter cells will differ in
chromosome number, resulting
in a mosaic karyotype
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
Couples who are at risk of passing on the
allele for muscular dystrophy may utilize
________ to minimize the possibility.
20%
1.
20%
20%
3
4
20%
preimplantation
diagnosis
karyotyping to evaluate
the gametes prior to in
vitro fertilization
expansion mutation
technology
phenotypic treatment
all of the choices
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
The procedure that binds fluorescent dyes to
prepared chromosomes is called ________.
20%
20%
20%
20%
3
4
20%
1.
2.
3.
4.
spectral karyotyping
disjunction
inversion technology
phenotypic
treatment
5. restriction analysis
1
2
3
4
5
1
2
5
Two parents, both carriers for galactosemia, have
a child that is phenotypically normal; what is the
probability that the child is a carrier?
20%
1.
2.
3.
4.
5.
1
20%
20%
20%
3
4
20%
1 in 4 (25%)
1 in 2 (50%)
1 in 3 (33%)
2 in 3 (67%)
3 in 4 (75%)
2
3
4
5
1
2
5
While conducting reciprocal crosses with fly
eye color, Morgan observed that ________.
20%
1.
20%
20%
3
4
20%
white-eyed males did not find redeyed females sexually attractive
flies homozygous for white eyes did
not survive to sexual maturity
the F1 ratios were dependent on the
gender of the parent with white eyes
the white-eyed trait was lost to the
population by the end of the F4
generation
the parental source of the allele, as
with peas, did not influence the F1
ratios
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
Huntington's disease has been shown to be
caused by an expansion mutation, a
condition occurring when ________.
20%
1.
20%
20%
3
4
20%
a portion of one chromosome is
inserted into another
a gene becomes elongated following
the repetitive addition of small DNA
segments called repeats
a section of DNA is moved from one
homologous chromosome to the
other, producing abnormally long
and short chromosomes
homologous chromosomes fail to
separate, and then join end to end
none of the choices describes
expansion
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
How does the presence of the Y
chromosome direct the embryo to become
male?
20%
1.
20%
20%
3
4
20%
all the genes for the male phenotype are
found on the Y chromosome
the amount of estrogen produced by XY
cells is too small to activate the genes
directing female development, causing the
embryo to become male
the Y chromosome carries a gene for
testes formation; the testes then produce
testosterone, which activates genes on
numerous chromosomes
the combination of X and Y gene products
combine to form a receptor, which is
sensitive to the hormones produced by
the mother
biologists are uncertain, but the question
addresses an area of active research
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
If a man who is homozygous for an autosomaldominant condition has children with a woman who
does not carry genes for that condition, ________.
20%
1.
20%
20%
3
4
20%
all of their offspring will inherit
the condition, regardless of their
gender
three-quarters of their offspring
will inherit the condition
none of their offspring will inherit
the condition, but half will be
carriers
half of their offspring will inherit
the condition
half of their sons will inherit the
condition and half of their
daughters will be carriers
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
Comparisons of human and great ape
chromosomes suggest that ________.
20%
1.
20%
20%
3
4
20%
the two groups are, at best, distantly
related and have been evolving
separately for a long time
two ape chromosomes fused, reducing
the human chromosome number to one
pair less than the apes
chromosomal change is too disruptive to
be a component in evolutionary change
selection always opposes chromosomal
alteration, causing total number and
structure to be highly conserved
any similarities are coincidental, as
virtually no homologous regions exist
between any pair of chromosomes
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
Analysis of the pedigree for the descendants
of King George III and Louis II suggests that
________.
20%
1.
20%
20%
3
4
20%
Queen Victoria suffered from
hemophilia
hemophilia is caused by a
dominant allele carried on the X
chromosome
Hemophilia was introduced to
the European monarchy from
sources from France
Queen Victoria was a carrier for
hemophilia
males suffering from hemophilia
always died early in life without
leaving children
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
Since dominant alleles are always expressed and
detected, how can the persistence of autosomaldominant disorders be explained?
20%
1.
20%
20%
3
4
20%
many individuals with dominant
disorders have overcome the
challenges they present and have
decided to have children
some dominant alleles are not
expressed until after the age when
most people have reproduced
unless the symptoms of the disorder
prevent reproduction, the gene may
be passed on
some conditions are continually
reintroduced to a population through
spontaneous mutation
all of the choices
2.
3.
4.
5.
1
20%
2
3
4
5
1
2
5
Down syndrome ________.
20%
1.
2.
3.
20%
20%
3
4
20%
is observed only in females
is also known as trisomy 21
affects only the central
nervous system
results from a deletion
is a Y-linked disorder, passed
directly from father to son
4.
5.
1
20%
2
3
4
5
1
2
5