BSN 346 - Sherpath Week 9 Cellular Regulation Questions with Correct Answers Latest Update
2025/2026
A woman of advanced maternal age undergoes genetic testing during her pregnancy. If the
fetus has Down syndrome, how many chromosomes would the test identify?
23
45
46
47 - Answers 47
The typical child with Down syndrome has 3 copies of the 21st chromosome, which results in a
total of 47 chromosomes found in each cell.
Which response is most appropriate when the parents (both heterozygotes) of a child born with
cystic fibrosis ask the probability of future pregnancies resulting in a child inheriting the disease?
25%
50%
75%
100% - Answers 25%
A child that inherits an autosomal recessive disorder must receive the affected gene from both
parents. Using a Punnett square, the probability can be seen to be 25%.
RATIONALE FOR INCORRECT:
50%
50% would be the inheritance pattern of an autosomal dominant disease where one parent is
affected.
75%
75% would be the probability of having a child who does not have cystic fibrosis.
100%
,All children born to two parents who have an autosomal recessive disease will have the disease;
this would equate to 100% of the offspring.
What is the probability of having a child with cystic fibrosis if one parent has the disease and the
other is a carrier?
25%
50%
75%
100% - Answers 50%
The probability is 50% because the affected parent will pass on the gene to all children and the
other has a 50% chance of passing on the gene.
RATIONALE FOR INCORRECT:
25%
This would be the case if both parents were carriers.
75%
This is the probability of an unaffected child if both parents were carriers.
100%
This would be the case if both parents had the disease.
A newborn child is noted to have malodorous, musty urine and later shows signs of
developmental delay and seizures. Which disorder presents with these characteristics?
Sickle Cell
Phenylketonuria
Marfan Syndrome
Muscular Dystrophy - Answers Phenylketonuria
Phenylketonuria leads to buildup of toxic phenylalanine. This can be neurotoxic, causing brain
damage, developmental delay, and seizures. There is also a characteristic musty odor to the
urine.
,RATIONALE FOR INCORRECT:
Sickle Cell
Sickle cell causes painful crises, avascular necrosis, and anemia.
Marfan Syndrome
Marfan syndrome presents with long limbs and fingers and potentially serious aortic disease.
Muscular Dystrophy
Muscular dystrophy causes muscle weakness and wasting and cardiomyopathy.
A 70-year-old man and his 45-year-old wife have a child who is found to have a genetic disorder.
What signs and symptoms are likely to be seen in this child born to parents of advanced
maternal and paternal age?
Select all that apply.
Leukemia
Gowers Sign
Visual Problems
Hearing Disorders
Congenital Heart Defects - Answers Leukemia
Down syndrome is associated with both late maternal and paternal age. It has many
manifestations, including leukemia, visual problems (cataracts, strabismus), hearing disorders,
and congenital heart defects.
Visual Problems
Down syndrome is associated with both late maternal and paternal age. It has many
manifestations, including leukemia, visual problems (cataracts, strabismus), hearing disorders,
and congenital heart defects.
Hearing Disorders
, Down syndrome is associated with both late maternal and paternal age. It has many
manifestations, including leukemia, visual problems (cataracts, strabismus), hearing disorders,
and congenital heart defects.
Congenital Heart Defects
Down syndrome is associated with both late maternal and paternal age. It has many
manifestations, including leukemia, visual problems (cataracts, strabismus), hearing disorders,
and congenital heart defects.
RATIONALE FOR INCORRECT:
Gowers Sign
Gowers sign is seen in Duchenne muscular dystrophy, which is not associated with advanced
parental age.
Which disease is known to have a strong familial association, attributed to several different
genes, and requires early and increased screening?
Colon Cancer
Cystic Fibrosis
Hemophilia A
Marfan Syndrome - Answers Colon Cancer
Several genes have been identified that confer an increased risk for colon cancer, so earlier and
increased screening may be considered based on history of a first degree relative.
RATIONALE FOR INCORRECT:
Cystic Fibrosis
As an autosomal recessive disorder, a single gene causes cystic fibrosis, not several genes.
Hemophilia A
As an X-linked recessive disorder, a single gene causes hemophilia A, not several genes.
2025/2026
A woman of advanced maternal age undergoes genetic testing during her pregnancy. If the
fetus has Down syndrome, how many chromosomes would the test identify?
23
45
46
47 - Answers 47
The typical child with Down syndrome has 3 copies of the 21st chromosome, which results in a
total of 47 chromosomes found in each cell.
Which response is most appropriate when the parents (both heterozygotes) of a child born with
cystic fibrosis ask the probability of future pregnancies resulting in a child inheriting the disease?
25%
50%
75%
100% - Answers 25%
A child that inherits an autosomal recessive disorder must receive the affected gene from both
parents. Using a Punnett square, the probability can be seen to be 25%.
RATIONALE FOR INCORRECT:
50%
50% would be the inheritance pattern of an autosomal dominant disease where one parent is
affected.
75%
75% would be the probability of having a child who does not have cystic fibrosis.
100%
,All children born to two parents who have an autosomal recessive disease will have the disease;
this would equate to 100% of the offspring.
What is the probability of having a child with cystic fibrosis if one parent has the disease and the
other is a carrier?
25%
50%
75%
100% - Answers 50%
The probability is 50% because the affected parent will pass on the gene to all children and the
other has a 50% chance of passing on the gene.
RATIONALE FOR INCORRECT:
25%
This would be the case if both parents were carriers.
75%
This is the probability of an unaffected child if both parents were carriers.
100%
This would be the case if both parents had the disease.
A newborn child is noted to have malodorous, musty urine and later shows signs of
developmental delay and seizures. Which disorder presents with these characteristics?
Sickle Cell
Phenylketonuria
Marfan Syndrome
Muscular Dystrophy - Answers Phenylketonuria
Phenylketonuria leads to buildup of toxic phenylalanine. This can be neurotoxic, causing brain
damage, developmental delay, and seizures. There is also a characteristic musty odor to the
urine.
,RATIONALE FOR INCORRECT:
Sickle Cell
Sickle cell causes painful crises, avascular necrosis, and anemia.
Marfan Syndrome
Marfan syndrome presents with long limbs and fingers and potentially serious aortic disease.
Muscular Dystrophy
Muscular dystrophy causes muscle weakness and wasting and cardiomyopathy.
A 70-year-old man and his 45-year-old wife have a child who is found to have a genetic disorder.
What signs and symptoms are likely to be seen in this child born to parents of advanced
maternal and paternal age?
Select all that apply.
Leukemia
Gowers Sign
Visual Problems
Hearing Disorders
Congenital Heart Defects - Answers Leukemia
Down syndrome is associated with both late maternal and paternal age. It has many
manifestations, including leukemia, visual problems (cataracts, strabismus), hearing disorders,
and congenital heart defects.
Visual Problems
Down syndrome is associated with both late maternal and paternal age. It has many
manifestations, including leukemia, visual problems (cataracts, strabismus), hearing disorders,
and congenital heart defects.
Hearing Disorders
, Down syndrome is associated with both late maternal and paternal age. It has many
manifestations, including leukemia, visual problems (cataracts, strabismus), hearing disorders,
and congenital heart defects.
Congenital Heart Defects
Down syndrome is associated with both late maternal and paternal age. It has many
manifestations, including leukemia, visual problems (cataracts, strabismus), hearing disorders,
and congenital heart defects.
RATIONALE FOR INCORRECT:
Gowers Sign
Gowers sign is seen in Duchenne muscular dystrophy, which is not associated with advanced
parental age.
Which disease is known to have a strong familial association, attributed to several different
genes, and requires early and increased screening?
Colon Cancer
Cystic Fibrosis
Hemophilia A
Marfan Syndrome - Answers Colon Cancer
Several genes have been identified that confer an increased risk for colon cancer, so earlier and
increased screening may be considered based on history of a first degree relative.
RATIONALE FOR INCORRECT:
Cystic Fibrosis
As an autosomal recessive disorder, a single gene causes cystic fibrosis, not several genes.
Hemophilia A
As an X-linked recessive disorder, a single gene causes hemophilia A, not several genes.
