which of the following statements about rh incompatibility is true

HESI LPN

HESI Maternal Newborn

1. Which of the following statements about Rh incompatibility is true?

A. Rh incompatibility occurs most commonly during a woman’s first pregnancy.
B. Rh incompatibility is an untreatable condition that leaves a woman infertile for the rest of her life.
C. Rh incompatibility is an abnormality that is transmitted from generation to generation and carried by a sex chromosome.
D. Rh incompatibility occurs due to antibodies transmitted to a fetus during subsequent deliveries causing brain damage or death.

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.

2. A primigravida is being monitored at the prenatal clinic for preeclampsia. Which finding is of greatest concern to the nurse?

A. Blood pressure (BP) increased to 138/86 mm Hg.
B. Weight gain of 0.5 kg during the past 2 weeks.
C. Dipstick value of 3+ for protein in her urine.
D. Pitting pedal edema at the end of the day.

Correct answer: C

Rationale: The correct answer is C. Proteinuria, indicated by a dipstick value of 3+ in the urine, is a significant concern in a patient being monitored for preeclampsia. Proteinuria is a key diagnostic criterion for preeclampsia, and a value of 3+ signifies a substantial amount of protein in the urine, warranting further evaluation. While an increase in blood pressure to 138/86 mm Hg is slightly elevated, it does not meet the diagnostic threshold for severe hypertension in preeclampsia. A weight gain of 0.5 kg over 2 weeks is within normal limits and not as concerning as significant rapid weight gain. Pitting pedal edema, though common in pregnancy, is not a specific indicator of preeclampsia and is considered a less concerning finding compared to significant proteinuria.

3. A nurse is caring for a newborn who is 6 hours old and has a bedside glucometer reading of 65 mg/dL. The newborn’s mother has type 2 diabetes mellitus. Which of the following actions should the nurse take?

A. Obtain a blood sample for a serum glucose level
B. Feed the newborn immediately
C. Administer 50 mL of dextrose solution IV
D. Reassess the blood glucose level prior to the next feeding

Correct answer: D

Rationale: A bedside glucometer reading of 65 mg/dL is within the normal range for a newborn. Reassessing the blood glucose level prior to the next feeding ensures ongoing monitoring without unnecessary intervention. Obtaining a blood sample for a serum glucose level (Choice A) is not necessary as the initial reading is normal. Feeding the newborn immediately (Choice B) may not be indicated and could lead to unnecessary interventions. Administering dextrose solution IV (Choice C) is not warranted as the glucose level is within the normal range and does not require immediate correction.

4. Which of the following statements is true of mutations?

A. Mutations can only occur by chance.
B. Mutations produce sperm and ova cells.
C. Mutations occur through radiation or other environmental influences.
D. Mutations help adenine combine with guanine to form the single spiral structure of DNA.

Correct answer: C

Rationale: The correct answer is C. Mutations can occur due to environmental influences such as radiation, chemicals, or other external factors, leading to changes in the DNA sequence. Choice A is incorrect because mutations can also occur due to errors in DNA replication, not solely by chance. Choice B is incorrect as mutations affect the DNA sequence itself, not the production of specific cells. Choice D is incorrect because mutations involve changes in the DNA sequence and do not specifically involve the formation of the DNA structure.

5. In the structure of deoxyribonucleic acid (DNA), which of the following bases combines with thymine?

A. Cytosine
B. Adenine
C. Rhodamine
D. Serine

Correct answer: B

Rationale: The correct answer is B: Adenine. In the structure of DNA, adenine pairs with thymine through hydrogen bonding, forming one of the complementary base pairs that make up the double helix structure of DNA. Cytosine pairs with guanine, not thymine. Rhodamine and serine are not DNA bases and do not participate in DNA base pairing. Therefore, choices A, C, and D are incorrect.