Name ______________________________________ Date ____________ Period _____
HONORS BIOLOGY
Chromosomal Abnormalities
Directions: Use your class notes and/or textbook to answer the following questions about
chromosomal abnormalities.
1. Chromosomes that are paired together because they are similar in size, shape, and
the genes they carry are called ________________________.
a. analogous chromosomes
b. univalent chromosomes
c. homologous chromosomes
d. tetrads
2. A picture of chromosomes arranged by size and centromere location that can
reveal abnormalities is called a __________________.
a. karyocature
b. karyotype
c. chromotype
d. chromomere
3. Out of what kind of material(s) are chromosomes made?
a. protein only
b. DNA only
c. scientists do not know yet
d. DNA and protein
4. Based on the following karyotype, what can you conclude about this person?
a.
b.
c.
d.
They are a normal female.
They are a normal male.
They have Edward’s Syndrome
They have Down’s Syndrome
5. A person with Cri-du-Chat Syndrome is
a. missing chromosome # 5
b. has trisomy 18
c. missing part of chromosome # 5
d. has trisomy 21
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6. Another name for trisomy 13 is
a. Patau Syndrome
b. Down’s Syndrome
c. Edward’s Syndrome
d. Klinefelter’s Syndrome
7. Klinefelter’s Syndrome is caused by the presence of
a. an extra Y-chromosome (XYY)
b. an extra X-chromosome (XXY)
c. a missing X-chromosome ( _X)
d. a third 21st chromosome
8. The odds of a 20-year-old woman having a child with Down’s Syndrome is
________________.
a. 1 out of 50
b. 1 out of 1500
c. 1 out of 350
d. none of the above
9. The odds of a 43-year-old-woman having a child with Down’s Syndrome is
________________.
a. 1 out of 50
b. 1 out of 1500
c. 1 out of 350
d. none of the above
10. Non-sex chromosomes are called ________________________.
a. autosomes
b. autochromes
c. chromomeres
d. chromotypes
11. An accident of meiosis or mitosis, in which both members of a pair of
homologous chromosomes or both sister chromatids fail to move apart properly is
called ______________________.
a. autosomal disjunction
c. nondisjunction
b. disjunction
d. none of the above
12. How many chromosomes do normal human beings have?
a. 22 pairs of chromosomes
b. 23 chromosomes
c. 46 pairs of chromosomes
d. 23 pairs of chromosomes
USE THE FOLLOWING INFORMATION TO ANSWER THE NEXT TWO
QUESTIONS. In humans, unusual numbers of sex chromosomes sometimes occur, such
as XO = female, usually sterile; XXX = female, low fertility rate; XXY = male, tall and
sexually underdeveloped; XX = female, normal; and XY = male, normal.
13. What phenomenon is responsible for the unusual chromosome numbers?
a. nondisjunction
c. tetrad formation
b. anaphase
d. crossing over
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14. What kind of logical conclusion can be drawn from studies of these disorders of
chromosome number?
a. The two X chromosomes are necessary to produce females.
b. The number of X chromosomes determines the sex of the child.
c. The Y chromosome does not carry genetic information.
d. The presence of a Y chromosome determines sex in humans.
15. What sex chromosomes would you expect to find in someone with Jacob’s
syndrome?
a. XYY
d. X
b. Trisomy-21
e. XXX
c. XXY
16. Amniocentesis was performed on a woman. The withdrawn fluid underwent
biochemical analysis and the fetal cells were cultured. A karyotype was done.
The child was discovered to have an extra #21 chromosome. What is the
diagnosis?
a. Down Syndrome
d. Triplo-X Syndrome
b. Turner’s Syndrome
e. Klinefelter’s Syndrome
c. Jacob’s Syndrome
17. Down Syndrome occurs more frequently in gametes produced by parents nearing
middle age. A 40-year old woman who discovers she is pregnant and is worried
about the possibility of her baby having Down Syndrome should request
a. A special diet during pregnancy.
b. Training for the care of a Down syndrome child.
c. Examination by amniocentesis.
d. Karyotypes for herself and her husband.
18. A normal human male would be expected to have how many Barr bodies in his
cells?
a. 0
c. 2
b. 1
d. 3
19. A normal human female would be expected to have how many Barr bodies in his
cells?
a. 0
c. 2
b. 1
d. 3
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Match the following karyotypes with the appropriate disorder.
20.
a. Down’s Syndrome
b. Edward’s Syndrome
c. Cri-du-Chat
d. Klinefelter’s Syndrome
e. Jacob’s Syndrome
f. Patau Syndrome
21.
g. Turner’s Syndrome
h. Normal female
i. Normal male
22.
23.
24.
25.
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