Nokea
Conjoined twins are formed at which point of gestation?
- A. Immediately after fertilization
- B. At the time of implantation
- C. At about 13 to 15 days after conception
- D. In the blastocyst stage
Correct Answer: C
Rationale: Conjoined twins are formed at about 13 to 15 days after conception when the embryonic disc undergoes incomplete splitting. At this stage, the cells have already differentiated into different layers, making separation challenging. Immediately after fertilization (choice A) is too early for conjoined twins to form. At the time of implantation (choice B) is when the blastocyst implants into the uterine wall, but conjoined twins are not formed at this point. In the blastocyst stage (choice D), the cells are still in the process of organizing and have not yet differentiated into distinct layers. Therefore, choice C is the correct answer as it aligns with the timing of conjoined twin formation during embryonic development.
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You are observing for fetal heart rate (FHR) accelerations in a nonstress test (NST) for a woman who is 26 weeks pregnant. The average FHR baseline is 145 to 155 beats per minute (bpm). Within 20 minutes, the FHR accelerated to 165 bpm six times, for 10 to 15 seconds. How should you interpret this information?
- A. Results are nonreassuring, and another 20 minutes of monitoring is needed.
- B. Results are nonreassuring because of too few accelerations within the time period.
- C. Results are reassuring because the FHR accelerated by 10 bpm for 10 seconds.
- D. Results are reassuring because the fetus was inactive during the monitoring.
Correct Answer: C
Rationale: FHR accelerations of at least 10 bpm for 10 seconds are considered reassuring.
What protects the blood vessels in a healthy umbilical cord?
- A. None
- B. Wharton's jelly.
- C. None
- D. None
Correct Answer: B
Rationale: Wharton's jelly provides structural support and protection.
At which point in the pregnancy can a woman first feel fetal movement (quickening)?
- A. 12 weeks
- B. 16 weeks
- C. 20 weeks
- D. 24 weeks
Correct Answer: C
Rationale: The correct answer is C (20 weeks) because quickening, the first perception of fetal movement by the mother, typically occurs around this time. At 20 weeks, the fetus is large enough for its movements to be noticeable to the mother. Before 20 weeks, the fetus is too small and the movements are not strong enough to be felt. Choices A, B, and D are incorrect because they are too early in the pregnancy for the mother to feel fetal movement. By 20 weeks, the fetus has developed enough for the mother to perceive its movements, making option C the correct answer.
The time period immediately following fertilization results in which circumstance?
- A. Formation of a zygote that contains the haploid number of chromosomes
- B. Formation of an embryo that contains the haploid number of chromosomes
- C. Formation of a zygote that contains the diploid number of chromosomes
- D. Formation of a 16-cell morula
Correct Answer: C
Rationale: The correct answer is C: Formation of a zygote that contains the diploid number of chromosomes. After fertilization, the sperm and egg combine to form a zygote with a complete set of chromosomes (diploid). This is crucial for genetic diversity and proper development.
Choice A is incorrect because a zygote is diploid, not haploid. Choice B is incorrect as an embryo is formed later in development and contains diploid chromosomes. Choice D is incorrect because a morula is a stage where the zygote undergoes several rounds of cell division, but it does not yet contain a full diploid set of chromosomes.
A female patient is concerned about an inability to become pregnant after trying for 1 year. Which information collected during a health history causes the nurse the greatest amount of concern about possible infertility?
- A. The patient works as a ballroom dance instructor.
- B. The patient is turning 37 years old this year.
- C. The patient has hot flashes and mood swings.
- D. The patient was treated for a pelvic inflammatory disease while in college.
Correct Answer: C
Rationale: The correct answer is C because hot flashes and mood swings can indicate hormonal imbalances, which are common causes of infertility. This symptom suggests potential issues with ovulation or other reproductive system functions. Choice A is irrelevant to infertility. Choice B, age alone does not indicate infertility. Choice D, a history of pelvic inflammatory disease can cause infertility, but symptoms indicating current hormonal imbalances are of more immediate concern.