dizygotic dz twins run in families

HESI LPN

Maternity HESI Test Bank

1. Do dizygotic (DZ) twins run in families?

A. Yes
B. No
C. Rarely
D. Never

Correct answer: A

Rationale: Yes, dizygotic (DZ) twins can run in families. This is due to genetic factors that influence hyperovulation, where a woman releases multiple eggs during her menstrual cycle. This genetic predisposition can be passed down through generations, increasing the likelihood of having dizygotic twins. Choices B, C, and D are incorrect because the statement that dizygotic twins run in families is true, as supported by scientific evidence. It is important to note that while the genetic predisposition for dizygotic twins can run in families, it does not guarantee that every generation will have twins, as other factors also play a role in twin pregnancies.

2. What maternal factor should the nurse identify as having the greatest impact on the development of spina bifida occulta in a newborn?

A. Short interval between pregnancies
B. Folic acid deficiency
C. Preeclampsia
D. Tobacco use

Correct answer: B

Rationale: Folic acid deficiency during pregnancy is a well-known risk factor for neural tube defects, including spina bifida occulta, making supplementation critical in prenatal care. Folic acid plays a crucial role in neural tube formation during early pregnancy. Short intervals between pregnancies do not directly impact the development of spina bifida occulta. Preeclampsia is a hypertensive disorder of pregnancy and is not directly linked to spina bifida occulta. While tobacco use during pregnancy has various adverse effects, it is not the primary factor influencing the development of spina bifida occulta in newborns.

3. What causes cystic fibrosis?

A. Sex-linked abnormality.
B. Abnormality in the 21st pair of chromosomes.
C. Recessive gene.
D. Single segment found only on the Y chromosome.

Correct answer: C

Rationale: Cystic fibrosis is a genetic disorder caused by inheriting two copies of a recessive gene, one from each parent. This means that both parents must carry at least one copy of the faulty gene for a child to inherit the condition. Choice A is incorrect because cystic fibrosis is not linked to the sex chromosomes. Choice B is incorrect as cystic fibrosis is not caused by an abnormality in the 21st pair of chromosomes but by a specific gene mutation. Choice D is also incorrect as cystic fibrosis is not related to the Y chromosome, which is specific to males.

4. Which of the following statements is true of mutations?

A. Mutations can only occur by chance.
B. Mutations produce sperm and ova cells.
C. Mutations occur through radiation or other environmental influences.
D. Mutations help adenine combine with guanine to form the single spiral structure of DNA.

Correct answer: C

Rationale: The correct answer is C. Mutations can occur due to environmental influences such as radiation, chemicals, or other external factors, leading to changes in the DNA sequence. Choice A is incorrect because mutations can also occur due to errors in DNA replication, not solely by chance. Choice B is incorrect as mutations affect the DNA sequence itself, not the production of specific cells. Choice D is incorrect because mutations involve changes in the DNA sequence and do not specifically involve the formation of the DNA structure.

5. The nurse has received a report regarding a client in labor. The woman’s last vaginal examination was recorded as 3 cm, 30%, and –2. What is the nurse’s interpretation of this assessment?

A. Cervix is effaced 3 cm and dilated 30%; the presenting part is 2 cm above the ischial spines.
B. Cervix is dilated 3 cm and effaced 30%; the presenting part is 2 cm above the ischial spines.
C. Cervix is effaced 3 cm and dilated 30%; the presenting part is 2 cm below the ischial spines.
D. Cervix is dilated 3 cm and effaced 30%; the presenting part is 2 cm below the ischial spines.

Correct answer: B

Rationale: The correct interpretation of the assessment provided is that the cervix is dilated 3 cm and effaced 30%; the presenting part is 2 cm above the ischial spines. In the given assessment, the measurements are ordered as dilation, effacement, and station. Choice A is incorrect as it wrongly places the presenting part below the ischial spines. Choice C is incorrect because it places the presenting part below the ischial spines. Choice D is also incorrect as it incorrectly states that the presenting part is below the ischial spines, even though it correctly mentions the dilation and effacement of the cervix.