A woman gave birth to a 7-pound, 6-ounce infant girl 1 hour ago. The birth was vaginal and the estimated blood loss (EBL) was 1500 ml. When evaluating the woman's vital signs, which finding would be of greatest concern to the nurse?

Correct Answer: A

Rationale: An estimated blood loss (EBL) of 1500 ml following a vaginal birth is significant and can lead to hypovolemia. The vital signs provided in option A (Temperature 37.9°C, heart rate 120 bpm, respirations 20 breaths per minute, and blood pressure 90/50 mm Hg) indicate tachycardia and hypotension, which are concerning signs of hypovolemia due to excessive blood loss. Tachycardia is the body's compensatory mechanism to maintain cardiac output in response to decreased blood volume, and hypotension indicates inadequate perfusion. Options B, C, and D do not exhibit the same level of concern for hypovolemia. Option B shows tachypnea, which can be a result of pain or anxiety postpartum. Option C and D have vital signs within normal limits, which are not indicative of the body's response to significant blood loss.

Correct Answer: D

Rationale: Huntington's disease is a fatal genetic neurologic disorder characterized by progressive nerve cell degeneration in the brain. It typically manifests in middle age with symptoms such as involuntary movements, cognitive decline, and psychiatric disturbances. Tay-Sachs disease (Choice A) is a genetic disorder that primarily affects the nervous system in early childhood, not middle age. Duchenne muscular dystrophy (Choice B) is a genetic disorder that primarily affects muscle function and usually presents in early childhood. Hemophilia (Choice C) is a genetic disorder related to blood clotting, and its onset is not typically in middle age.

Correct Answer: D

Rationale: Rh incompatibility occurs when the mother's antibodies attack the fetus's red blood cells, leading to serious complications, usually in subsequent pregnancies. Choice A is incorrect because Rh incompatibility often occurs in subsequent pregnancies, not necessarily the first one. Choice B is incorrect as Rh incompatibility does not render a woman infertile but can lead to complications during pregnancies. Choice C is incorrect as Rh incompatibility is not carried by a sex chromosome but involves the Rh factor on red blood cells.

Correct Answer: B

Rationale: Human cells typically contain 46 chromosomes organized into 23 pairs. This is the correct number for a normal human cell. Choices A, C, and D are incorrect because they do not represent the typical chromosome count in human cells.

Correct Answer: D

Rationale: Hegar's sign, which is a softening of the lower uterine segment, is considered a probable sign of pregnancy as it indicates changes in the cervix and uterus that occur during pregnancy. Amenorrhea, the absence of menstruation, is a common early sign of pregnancy but can also be due to other factors. Morning sickness, nausea and vomiting, can be a sign of early pregnancy but is not as specific as Hegar's sign. Breast tenderness is a common symptom in early pregnancy due to hormonal changes, but it is not as definitive as Hegar's sign in indicating pregnancy.

Correct Answer: C

Rationale: The correct answer is 'Motility.' Motility refers to the ability of cells or organisms to move by themselves, often through the use of specialized structures like flagella or cilia. Mitosis (Choice A) and Meiosis (Choice B) are processes related to cell division and genetic recombination, respectively, not self-propulsion. Mutation (Choice D) refers to changes in the DNA sequence and is not related to self-propulsion.

Correct Answer: A

Rationale: The correct answer is A: 'They regulate the development of traits.' Genes play a crucial role in regulating the development of traits by encoding proteins that control various bodily functions and characteristics. This process involves gene expression and the production of proteins that ultimately determine an individual's traits. Choice B is incorrect because genes do not have a direct role in preventing foreign particles from entering the body; this function is primarily carried out by the immune system. Choice C is incorrect as genes do not specifically work with lutein to influence development; genes operate independently to regulate trait expression. Choice D is incorrect as genes are not responsible for transferring oxygen in the bloodstream; this function is carried out by red blood cells and hemoglobin.

Correct Answer: A

Rationale: To ensure adequate installation of the ophthalmic erythromycin 5% ointment in a newborn, the nurse should instill a thin ribbon into each lower conjunctival sac. This method helps to ensure proper distribution and effectiveness of the medication to prevent neonatal conjunctivitis. Choices B, C, and D are incorrect. Occluding the inner canthus after retracting the eyelids, mummy wrapping the infant, or stabilizing the instilling hand on the neonate's head are not appropriate actions for ensuring the proper installation of the ointment.

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.