Maternity HESI Test Bank

Correct Answer: C

Rationale: Uterine atony is the most likely cause of bleeding 4 hours after delivery, especially after delivering a macrosomic infant and augmenting labor with oxytocin. Uterine atony is characterized by the inability of the uterine muscles to contract effectively after childbirth, leading to excessive bleeding. The other options, such as retained placental fragments (A), unrepaired vaginal lacerations (B), and puerperal infection (D), are less likely causes of postpartum hemorrhage in this scenario. Retained placental fragments can cause bleeding, but this typically presents earlier than 4 hours postpartum. Unrepaired vaginal lacerations would likely be evident sooner and not typically result in significant bleeding. Puerperal infection is not a common cause of immediate postpartum hemorrhage unless there are other signs of infection present.

Correct Answer: D

Rationale: After mitosis, the genetic code is typically preserved and remains identical in the new cells. However, mutations can occur due to radiation or environmental influences, leading to changes in the DNA sequence and potentially altering the genetic code. Therefore, the correct answer is 'mutations.' Choices A, B, and C are incorrect because reductions, expulsions, and conceptions do not accurately describe the changes in the genetic code that can result from external factors. Mutations are the only option that reflects the alteration in the genetic code caused by external influences, making it the correct choice in this context.

Correct Answer: D

Rationale: Malodorous discharge is a common symptom of trichomoniasis caused by the Trichomonas vaginalis parasite. It is typically described as frothy, greenish-yellow, and malodorous. Choices A, B, and C are incorrect findings associated with other conditions. Thick, white vaginal discharge is more characteristic of a yeast infection; urinary frequency may be seen in urinary tract infections; and vulvar lesions are commonly seen in herpes simplex virus infections.

Correct Answer: D

Rationale: The correct answer is the sex chromosome received from the father. The father contributes either an X or Y chromosome, which determines the child's sex. This occurs at the moment of fertilization when the sperm carrying either an X (resulting in a female) or Y (resulting in a male) chromosome fertilizes the egg. Choices A, B, and C are incorrect because the presence of teratogens at the time of conception or ovulation does not determine the child's sex. While the sex chromosome received from the mother is important, it is the father's contribution that ultimately determines the child's sex.

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.