Nokea
What is the central layer of the embryo from which the bones and muscles develop?
- A. neural tube
- B. mesoderm
- C. ectoderm
- D. umbilical cord
Correct Answer: B
Rationale: The correct answer is mesoderm. The mesoderm is the middle layer of the embryo that gives rise to the bones, muscles, and other connective tissues. The neural tube (choice A) develops into the nervous system, not bones and muscles. The ectoderm (choice C) forms the skin and nervous system, not bones and muscles. The umbilical cord (choice D) is a structure that connects the developing fetus to the placenta; it is not a layer of the embryo that gives rise to bones and muscles.
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A prenatal educator is teaching a class about false labor. Which of the following information should the educator include?
- A. Contractions will become more intense with walking
- B. There will be dilation and effacement of the cervix
- C. There will be bloody show
- D. Contractions will become temporarily regular
Correct Answer: D
Rationale: The correct answer is D. False labor contractions, also known as Braxton Hicks contractions, are typically irregular and do not lead to cervical dilation or effacement. They are often described as sporadic and temporary, becoming temporarily regular. Choices A, B, and C are incorrect because false labor contractions do not intensify with activity, do not cause cervical changes like dilation and effacement, and are not associated with the presence of a bloody show.
Examination reveals that the laboring client's cervix is dilated to 2 centimeters, 70% effaced with the presenting part at -2 station. The client tells the nurse, 'I need my epidural now, this hurts.' The nurse's response to the client is based on which information?
- A. The client will need to be catheterized before the epidural can be administered.
- B. Administering an epidural at this point would slow down the labor process.
- C. The client should be dilated to at least 8 centimeters before receiving an epidural.
- D. The baby needs to be at a zero station before an epidural can be administered.
Correct Answer: B
Rationale: Administering an epidural too early in labor, especially at 2 cm dilation, can slow down the progress of labor. It is usually recommended to wait until labor is more established. Choice A is incorrect because catheterization is not a prerequisite for epidural administration. Choice C is incorrect as waiting until 8 cm dilation is not a standard requirement for epidural administration. Choice D is incorrect because the baby's station being at zero is not a strict criterion for epidural administration.
Before meiosis, a sperm cell:
- A. contains 46 chromosomes.
- B. contains two X chromosomes.
- C. is significantly larger than an egg cell.
- D. contains both an X and a Y chromosome.
Correct Answer: A
Rationale: Before meiosis, a sperm cell contains 46 chromosomes. This is because sperm cells, like other somatic cells, have a diploid number of chromosomes. During meiosis, the number of chromosomes is halved to 23 to combine with an egg cell during fertilization. Choice B is incorrect because a sperm cell carries either an X or a Y chromosome, not both (Choice D). Choice C is incorrect as sperm cells are generally smaller than egg cells, which is an adaptation that aids in motility and penetration of the egg during fertilization.
According to a study conducted in 2013 by Fellman, what affects the chances of having twins?
- A. Increase when a woman conceives at a younger age.
- B. Increase with parental age.
- C. Decrease with the frequency of intercourse before conception.
- D. Decrease with the use of fertility drugs.
Correct Answer: B
Rationale: The correct answer is B. According to the study by Fellman in 2013, the chances of having twins actually increase with parental age. Choice A is incorrect as the study does not specify a younger age for conceiving to increase the chances of twins. Choice C is incorrect as the frequency of intercourse before conception is not a highlighted factor in the study. Choice D is also incorrect as the study does not discuss the impact of fertility drugs on the likelihood of having twins.
A client is in the second stage of labor. Which of the following manifestations should the nurse expect?
- A. The client expels the placenta
- B. The client experiences gradual dilation of the cervix
- C. The client begins having regular contractions
- D. The client delivers the newborn
Correct Answer: D
Rationale: During the second stage of labor, the cervix is fully dilated, and the client delivers the newborn. The expulsion of the placenta occurs during the third stage of labor, not the second stage. Regular contractions typically begin in the first stage of labor, not the second. Gradual dilation of the cervix occurs during the first stage of labor, specifically during the active phase.