Nursing Unit 7 Exam Study Guide University of
South Alabama Exam Prep & 100 Q&A MCQs
2026/2027
1. A graduate nursing student is reviewing chromosomal abnormalities. What is the term for an
error in which homologous chromosomes fail to separate during meiosis or mitosis?
A. Aneuploidy
B. Nondisjunction
C. Polyploidy
D. Translocation
Correct Answer: B
Rationale: Nondisjunction is an error in which homologous chromosomes or sister chromatids
fail to separate normally during meiosis or mitosis. Aneuploidy is the result of nondisjunction
and refers to cells that do not contain a multiple of 23 chromosomes. Polyploidy occurs when a
cell has more than the diploid number of chromosomes. Translocation refers to the
interchanging of genetic material between nonhomologous chromosomes.
2. A healthcare professional is assessing a child with complete trisomy of the twenty-first
chromosome. Which findings should the professional expect?
A. Widely spaced nipples, reduced carrying angle at the elbow, and sparse body hair
,B. An IQ of 25 to 70, low nasal bridge, protruding tongue, and flat, low-set ears
C. High-pitched voice, tall stature, gynecomastia, and an IQ of 60 to 90
D. Circumoral cyanosis, edema of the feet, short stature, and mental slowness
Correct Answer: B
Rationale: Down syndrome (trisomy 21) is characterized by an IQ of 25 to 70, a low nasal bridge,
epicanthal folds, a protruding tongue, flat low-set ears, and congenital heart defects in one-
third to one-half of live-born children. It is the most well-known aneuploidy in an autosome,
occurring in approximately 1 in 800 births.
3. Which of the following best describes the chromosomal abnormality responsible for Down
syndrome?
A. Trisomy of the 21st chromosome
B. Monosomy of the X chromosome
C. Trisomy of the 18th chromosome
D. Deletion of the short arm of chromosome 5
Correct Answer: A
Rationale: Down syndrome is caused by trisomy of the 21st chromosome (three copies instead
of two). Approximately 97% of cases are caused by nondisjunction during the formation of one
of the parent's gametes or during early embryonic development. About 3% result from
translocations. Risk increases with maternal age.
, 4. A patient is diagnosed with Turner syndrome. Which karyotype is characteristic of this
condition?
A. 47,XXY
B. 45,X
C. 47,21+
D. 46,XY
Correct Answer: B
Rationale: Turner syndrome is characterized by a 45,X karyotype (monosomy X). Individuals with
Turner syndrome often exhibit short stature, webbed neck, and gonadal dysgenesis, which leads
to infertility. It is a chromosomal disorder affecting females.
5. A patient is diagnosed with Klinefelter syndrome. Which karyotype is characteristic of this
condition?
A. 45,X
B. 47,XXY
C. 47,21+
D. 46,XX
Correct Answer: B