Maternity HESI Test Bank

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.

Correct Answer: A

Rationale: The correct answer is A: Cytosine with guanine. In the DNA double helix, cytosine always pairs with guanine forming a base pair, and adenine pairs with thymine. These complementary base pairs form the rungs of the ladder-like structure of DNA. Choice B, Rhodamine with biotin, is incorrect as they are not base pairs found in DNA. Choice D, Serine with tyrosine, is incorrect as they are amino acids, not DNA bases. Choice C, Diaminopurine with ribozyme, is also incorrect as ribozyme is an enzyme, not a base, and diaminopurine is not one of the standard bases found in DNA.

Correct Answer: A

Rationale: A low sperm count or lack of sperm is indeed one of the most common causes of infertility in men. Factors such as hormonal imbalances, genetic issues, reproductive anatomy problems, and lifestyle factors can also contribute to male infertility. Choice B is incorrect because a low sperm count is a prevalent issue among men facing infertility, making it a common problem. Choices C and D are incorrect as they do not accurately reflect the prevalence of low sperm count as a cause of infertility in men.

Correct Answer: B

Rationale: Amniocentesis is a diagnostic procedure used to detect genetic abnormalities in the fetus, such as chromosomal disorders like Down syndrome. It is not performed to induce abortion. The primary purpose of amniocentesis is to assess the genetic health of the fetus, not to determine the baby's gender (Choice C). While amniocentesis can provide information about the baby's health and development, it is not primarily used for monitoring fetal growth (Choice D). Therefore, the correct answer is B.

Correct Answer: B

Rationale: Applying a cap to the newborn's head is the correct action in this scenario. Newborns are at risk of heat loss due to their high surface area to volume ratio, and maintaining their body temperature is crucial to prevent hypothermia. Giving a warm bath can further increase heat loss and is not recommended. Repositioning the newborn may not address the primary concern of temperature regulation. While monitoring oxygen saturation is important, addressing thermal regulation takes precedence in this situation.