WGU D115 OBJECTIVE ASSESSMENT
(OA) EXAM 2025-2026 COMPLETE UNIT
1-UNIT 7 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH
RATIONALES
Which type of genetic disease affects males more frequently than females?
Sex-linked recessive
Autosomal recessive
Autosomal dominant
Sex-linked dominant - CORRECT ANSWER-Sex-Linked recessive. Since males only
have one X and one Y, if the affected chromosome has the illness, it will be expressed.
In which two conditions are chromosomal abnormalities the leading known cause?
Intellectual disability
Respiratory disorders
Fetal miscarriage
Cardiovascular disease
Mental illness
,WGU D115 OBJECTIVE ASSESSMENT
(OA) EXAM 2025-2026 COMPLETE UNIT
1-UNIT 7 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH
RATIONALES
Check My Answer - CORRECT ANSWER-Intellectual disability and fetal miscarriage.
Chromosome abnormalities are the leading known cause of intellectual disability and
fetal miscarriage.
What are three examples of prenatal diagnostic studies?
Drug-sensitivity testing
Chorionic villus sampling (CVS)
Microscopy of cervical mucosa
Preimplantation genetic testing (PGT)
Amniocentesis - CORRECT ANSWER-Chorionic villus sampling (CVS), amniocentesis,
and preimplantation genetic testing (PGT) are examples of prenatal diagnostic studies
and are performed in vitro. CVS is a form of genetic testing that provides genetic
information found in utero and is usually performed between weeks 11 and 14 of
pregnancy. An amniocentesis is a form of genetic testing that evaluates amniotic fluid
and is usually performed during the second trimester, between weeks 15 and 20 of
pregnancy. PGT is performed on the embryo prior to implantation.
, WGU D115 OBJECTIVE ASSESSMENT
(OA) EXAM 2025-2026 COMPLETE UNIT
1-UNIT 7 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH
RATIONALES
Which genetic disorder is characterized by the presence of a zygote having one
chromosome with a normal complement of genes and one chromosome with a missing
gene?
Klinefelter syndrome
Down syndrome
Cri du chat syndrome
Turner syndrome - CORRECT ANSWER-Cri du chat syndrome (translated as "cry of
the cat") is caused by a DNA deletion. This term describes the cry often heard from a
baby affected by the syndrome. Cri du chat syndrome can present as a microcephalic,
low birth-weight baby with a piercing cry.
How can an X-linked recessive disease skip generations?
Mothers cannot pass X-linked genes to their sons.
Females are hemizygous for the X chromosome.
The disease can be transmitted through female carriers.
(OA) EXAM 2025-2026 COMPLETE UNIT
1-UNIT 7 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH
RATIONALES
Which type of genetic disease affects males more frequently than females?
Sex-linked recessive
Autosomal recessive
Autosomal dominant
Sex-linked dominant - CORRECT ANSWER-Sex-Linked recessive. Since males only
have one X and one Y, if the affected chromosome has the illness, it will be expressed.
In which two conditions are chromosomal abnormalities the leading known cause?
Intellectual disability
Respiratory disorders
Fetal miscarriage
Cardiovascular disease
Mental illness
,WGU D115 OBJECTIVE ASSESSMENT
(OA) EXAM 2025-2026 COMPLETE UNIT
1-UNIT 7 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH
RATIONALES
Check My Answer - CORRECT ANSWER-Intellectual disability and fetal miscarriage.
Chromosome abnormalities are the leading known cause of intellectual disability and
fetal miscarriage.
What are three examples of prenatal diagnostic studies?
Drug-sensitivity testing
Chorionic villus sampling (CVS)
Microscopy of cervical mucosa
Preimplantation genetic testing (PGT)
Amniocentesis - CORRECT ANSWER-Chorionic villus sampling (CVS), amniocentesis,
and preimplantation genetic testing (PGT) are examples of prenatal diagnostic studies
and are performed in vitro. CVS is a form of genetic testing that provides genetic
information found in utero and is usually performed between weeks 11 and 14 of
pregnancy. An amniocentesis is a form of genetic testing that evaluates amniotic fluid
and is usually performed during the second trimester, between weeks 15 and 20 of
pregnancy. PGT is performed on the embryo prior to implantation.
, WGU D115 OBJECTIVE ASSESSMENT
(OA) EXAM 2025-2026 COMPLETE UNIT
1-UNIT 7 QUESTIONS AND CORRECT
DETAILED ANSWERS WITH
RATIONALES
Which genetic disorder is characterized by the presence of a zygote having one
chromosome with a normal complement of genes and one chromosome with a missing
gene?
Klinefelter syndrome
Down syndrome
Cri du chat syndrome
Turner syndrome - CORRECT ANSWER-Cri du chat syndrome (translated as "cry of
the cat") is caused by a DNA deletion. This term describes the cry often heard from a
baby affected by the syndrome. Cri du chat syndrome can present as a microcephalic,
low birth-weight baby with a piercing cry.
How can an X-linked recessive disease skip generations?
Mothers cannot pass X-linked genes to their sons.
Females are hemizygous for the X chromosome.
The disease can be transmitted through female carriers.
