Ch 14 pre-test ANSWERS
Multiple Choice
Identify the choice that best completes the statement or answers the question.
__A__ 1. 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.
Figure 14–1
__C__ 2. According to Figure 14–1, what is the approximate probability that a human offspring will be female?
a. 10%
b. 25%
c. 50%
d. 75%
__D__ 3. How many chromosomes are shown in a normal human karyotype?
a. 2
b. 23
c. 44
d. 46
__D__ 4. Sex-linked genes are located on
a. the autosomal chromosomes.
b. the X chromosome only.
c. the Y chromosome only.
d. both the X chromosome and the Y chromosome.
__C__ 5. Human males have
a. one X chromosome only.
b. two X chromosomes.
c. one X and one Y chromosome.
d. two Y chromosomes.
__B__ 6. A cat that has spots of more than one color
a.
b.
c.
d.
has no Barr bodies.
is probably female.
is probably male.
could be male or female.
__B__ 7. Which of the following pairs of genotypes result in the same phenotype?
a. IAIA and IAIB
b. IBIB and IBi
c. IBIB and IAIB
d. IBi and ii
Blood Type
A
B
AB
O
Blood Types
Combination of Alleles
IAIA or IAi
IBIB or IBi
IAIB
ii
Figure 14–2
__C__ 8. If a man with blood type A and a woman with blood type B produce an offspring, what might be the
offspring’s blood type?
a. AB or O
b. A, B, or O
c. A, B, AB, or O
d. AB only
___A_ 9. If the allele for having a white forelock is dominant, family members WITHOUT a white forelock are
a. homozygous recessive.
b. heterozygous.
c. homozygous dominant.
d. trisomal.
__A__ 10. Which of the following is caused by a dominant allele?
a. Huntington’s disease
b. colorblindness
c. cystic fibrosis
d. sickle-cell disease
__D__ 11. Which of the following diseases and conditions does not appear until late in a person’s life?
a. cystic fibrosis
b. sickle cell disease
c. colorblindness
d. Huntington disease
__A__ 12. Sickle cell disease is caused by a
a. change in one allele.
b. change in the size of a chromosome.
c. change in two proteins.
d. change in the number of chromosomes in a cell.
__B__ 13. In cystic fibrosis, a change in a single gene causes the protein called CFTR to
a. become less soluble.
b. fold improperly.
c. destroy the cell membrane.
d. transport sodium ions.
__C__ 14. Compared with normal hemoglobin, the hemoglobin of a person with sickle cell disease is
a. longer.
b. shorter.
c. less soluble.
d. more soluble.
__C__ 15. Because the X chromosome contains genes that are vital for normal development, no baby has been born
a. with one X chromosome.
b. with three X chromosomes.
c. without an X chromosome.
d. with four X chromosomes.
__A__ 16. Which of the following can be used to cut DNA so it can be studied?
a. restriction enzymes
b. gel electrophoresis
c. karyotypes
d. haplotypes
__A__ 17. Which piece of DNA would move fastest in gel electrophoresis? A segment that is
a. 100 base pairs long.
b. 1,000 base pairs long.
c. 5,000 base pairs long.
d. 100,000 base pairs long.
Figure 14–9
__B__ 18. What new field is described by the overlap area in the Venn diagram in Figure 14–9?
a. biotechnology
b. bioinformatics
c. gene therapy
d. genetic engineering
__B__ 19. The Human Genome Project is an attempt to
a. sequence every person’s DNA.
b. sequence the DNA of every human gene.
c. cure infectious human diseases.
d. identify all restriction enzymes.
__C__ 20. What prevents insurance companies from discriminating against people based on information derived from
genetic tests?
a. Only scientists can read the results of complicated genetic tests.
b. Genetic tests don’t show information about genetic disorders.
c. Discrimination based on genetic information is against the law.
d. People with genetic diseases cannot do business with private insurance companies.