Deck 6: Mosiacism

Question 1

A child's genetic disorder is attributed to trisomy.How would the nurse explain this concept to the parents?

A)"Trisomy is a mistake that occurs during chromosome sorting as the egg and sperm develop."
B)"Trisomy occurs when part of a chromosome is copied more than once."
C)"Trisomy occurs when part of a chromosome is lost."
D)"Trisomy occurs when a fertilized egg has 47 chromosomes instead of 46."

Answer 1

"Trisomy occurs when a fertilized egg has 47 chromosomes instead of 46."

Question 2

Which statements would the nurse educator evaluate as indicating a student's need for additional instruction on trisomic rescue?

A)"Trisomic rescue occurs when the extra chromosome is isolated and lost."
B)"The effect of trisomic rescue depends on when it occurs."
C)"In somatic cells it is best for trisomic rescue to take place later rather than earlier."
D)"In sex cells it is best for trisomic rescue to take place sooner rather than later."
E)"Trisomic rescue can be induced through ionizing radiation."

Answer 2

"Trisomic rescue occurs when the extra chromosome is isolated and lost."
"The effect of trisomic rescue depends on when it occurs."
"In sex cells it is best for trisomic rescue to take place sooner rather than later."

Question 3

The parents of a child who is mosaic for trisomy 21 ask if there is a way to identify the proportion of their child's cells that are affected.What is the nurse's best answer?

A)"There are several simple tests to determine the proportion of mosaic cells."
B)"The only reliable test is very expensive."
C)"Testing can be done in Europe,but not in the United States."
D)"Reliable testing can only be done on autopsy."

Answer 3

"Reliable testing can only be done on autopsy."

Question 4

Genetic testing of a placenta reveals mosaicism.What are the implications for the fetus?

A)The fetus must also have mosaicism.
B)There should be no effects on the fetus.
C)Stillbirth is more common.
D)Fetal growth may be retarded.
E)The fetus will spontaneously abort prior to the 20^th gestational week.

Question 5

An infant was born with a condition resulting from genetic nondisjunction.What information should the nurse consider when developing a teaching plan for the parents?

A)Nondisjunction rarely causes profound defects in the child.
B)Nondisjunction is associated with pregnancy in older women.
C)The primary cause of nondisjunction is fertilization with sperm from an older man.
D)The effects of nondisjunction are easily corrected with gene therapy.

Question 6

A couple has experienced three spontaneous abortions (SABs)before week 9 of gestation and one SAB at week 20.What should the nurse consider when preparing to counsel this couple?

A)The earlier the SAB,the more likely a rare genetic defect.
B)Most SABs are related to genetic changes.
C)Later-gestation SABs are more likely than early-gestation SABs to reflect genetic disorders that are seen in live newborns.
D)If a genetic defect was present in the first SAB,it is more likely to be present in subsequent SABs.
E)Trisomies,monosomy X,and polyploidy make up the majority of genetic abnormalities associated with SAB.
F)None of above

Question 7

A client's chorionic villus sampling (CVS)reveals mosaicism,but amniocentesis does not.How should the nurse evaluate these results?

A)An error in analyzing the results must have occurred because these two events cannot exist simultaneously.
B)The client has a condition called anaphase lag.
C)The client has a condition called confined placental mosaicism (CPM).
D)Mosaicism is present in the fetus,but not in the placenta.

Question 8

An infant's genetic disorder is a result of monosomy.What explanation would the nurse provide to the parents?

A)"Your baby is missing a chromosome."
B)"Your baby has an extra set of all the chromosomes."
C)"Your baby has an extra chromosome."
D)"Your baby's cells are haploid."

Question 9

A client is diagnosed with trisomy mosaicism.How does the nurse interpret this diagnosis?

A)Some of the client's cells have 46 chromosomes.
B)Some of the client's cells have 47 chromosomes.
C)All the client's cells have 48 chromosomes.
D)The client's somatic cells have 23 chromosomes.
E)The client's sex cells have 25 chromosomes.

Question 10

The nurse has provided a client with basic information about genetics.Which statement would indicate the client has understood the nurse's instruction?

A)"A gene that is mutated is called a wild-type gene."
B)"We get 23 sets of chromosomes from each parent."
C)"Each person has thousands of genes."
D)"The position of a gene is called its site."

Question 11

A woman has just experienced a spontaneous abortion.Which information would the nurse analyze before counseling the client?

A)What was the fetal gestational age?
B)Are malformations present?
C)What is the father's ethnicity?
D)What is the mother's age?
E)Is the fetus small for gestational age?

Question 12

A female nurse tells a genetics clinical nurse (GCN)that she would like to get pregnant,but that she has heard that nurses are at risk for having infants with environmentally induced genetic disorders.According to the research,how should the specialist reply?

A)"There was some concern about this some time ago,but it has all been disproven."
B)"The area of highest concern is the neurological intensive care unit."
C)"You should be more concerned about eating a healthy diet and avoiding alcohol."
D)"Studies have shown a higher risk in nurses who work in the operating room or emergency department."

Question 13

What information would the nurse educator include when explaining how mosaicism occurs?

A)Generalized mosaicism is more likely if the nondisjunction mistake happens in the first one or two divisions of the fertilized egg.
B)The type of cells involved in mosaicism is critical to the effects it will cause.
C)The effects of mosaicism are reduced if trisomic cells do not survive.
D)Earlier diagnosis of mosaicism will reduce the somatic effects.
E)Mosaicism affects cells only during meiotic division.

Question 14

A client's chorionic villus sampling (CVS)reveals the presence of trisomy.How would the nurse interpret this test result?

A)Nondisjunction has not occurred.
B)The fetus's organ systems are involved.
C)There is trisomy in the placenta.
D)There is trisomy in at least one fetal tissue.

Question 15

The parent of a child profoundly affected by a gene alteration says,"I don't understand how something so small can cause such problems." How should the nurse respond?

A)"The effects depend on the environment in which the child is raised."
B)"Some children are affected even more than your child."
C)"The degree of effect depends on which gene is damaged and what kind of damage is done."
D)"We don't think about how we are potentially changing our genes when we expose ourselves to chemical substances."