ATI RN
Pediatrics Genetics Questions
Question 1 of 5
Which of the following cannot be seen in triploidy?
Correct Answer: D
Rationale: 69, YYY (D) cannot occur in triploidy. Rationale: Triploidy (3n=69) results from dispermy or diploid gametes (e.g., XXY, XXX), but YYY requires three Y-bearing sperms, biologically implausible in humans.
Question 2 of 5
69 XYY occurs due to:
Correct Answer: A
Rationale: Dispermy (A) causes 69, XYY. Rationale: Two Y-bearing sperms (23, Y each) + egg (23, X) yield triploid 69, XYY; nondisjunction or endomitosis don’t fit.
Question 3 of 5
Expressivity can be described as:
Correct Answer: B
Rationale: Expressivity (B) is the variable degree of phenotype expression influenced by factors. Rationale: Unlike pleiotropy (A, multiple effects) or penetrance (C, all-or-none), expressivity explains severity variation (e.g., mild vs. severe in neurofibromatosis).
Question 4 of 5
The prolactin level of the young woman described in Question 1 is 1000 times higher than normal. The next test in her evaluation should be
Correct Answer: A
Rationale: Elevated prolactin (1000x normal) suggests a pituitary prolactinoma. Cranial MRI (A) is the next step to visualize the pituitary gland. Rationale: MRI detects adenomas; abdominal CT (B) or pelvic ultrasound (C) assess unrelated areas; uterine biopsy (D) and mammography (E) don’t address pituitary pathology.
Question 5 of 5
Successful treatment of nonspecific vulvovaginitis includes all of the following EXCEPT
Correct Answer: D
Rationale: Treatment includes loose clothing (B), sitz baths (C), and mild soap (D). Oral tetracycline is not indicated. Rationale: Topical estrogen (A) may help in severe cases; tetracycline is for bacterial infections, not nonspecific vulvovaginitis.