HESI Maternal Newborn

Correct Answer: B

Rationale: The correct answer is B: Intense abdominal pain. Pain is absent with placenta previa but can be agonizing with abruptio placentae. While bleeding may be present in varying degrees for both placental conditions, intense abdominal pain is a distinguishing feature of abruptio placentae. Uterine activity and cramping may be present with both placental conditions, but they are not the most prevalent clinical manifestation of abruptio placentae.

Correct Answer: D

Rationale: An amniocentesis in this scenario is most likely being performed to assess fetal lung maturity. This is necessary when considering early delivery due to macrosomia (large fetal size), which is a common concern in gestational diabetes. Evaluating fetal lung maturity is crucial to determine if the fetus's lungs are developed enough to support breathing independently outside the womb. The presence of a neural tube defect and chromosomal abnormalities are not typically assessed through amniocentesis in this situation, and determining the gender of the fetus is not the primary purpose of the procedure here.

Correct Answer: C

Rationale: Out of millions of sperm released during ejaculation, only a small fraction, about 1 in 1,000, will approach the ovum. This statement is true as sperm face many obstacles and challenges on their journey to reach and fertilize an ovum. Choice A is incorrect because the average count of sperm in an ejaculate is typically in the millions, not billions. Choice B is incorrect as sperm do not find the ovum by following the current of fluid; they navigate using other mechanisms. Choice D is incorrect because while some sperm may move randomly in the vagina, the ones that approach the ovum do so through a more purposeful and directed movement.

Correct Answer: C

Rationale: Down's syndrome, also known as trisomy 21, is caused by the presence of an extra chromosome on the 21st pair. Choice A is incorrect as alcohol abuse is not the cause of Down's syndrome. Choice B is incorrect because Down's syndrome is not related to sex-linked chromosomal abnormalities. Choice D is also incorrect as drug abuse by the mother during pregnancy is not the cause of Down's syndrome.

Correct Answer: A

Rationale: The typical sex chromosome pattern for females is XX. Females have two X chromosomes, which is represented as XX. Choice B (XYY) is incorrect as it represents the sex chromosome pattern for males with an extra Y chromosome. Choice C (XY) is the sex chromosome pattern for males. Choice D (XXY) represents a genetic disorder known as Klinefelter syndrome, where males have an extra X chromosome.