ATI RN
Pediatric Genetic Questions
Question 1 of 5
Imagine if the humans' diploid chromosomal complement is 10 instead of 46. What would the number of possible combinations of meiosis be:
Correct Answer: B
Rationale: The number of possible chromosome combinations in meiosis is 2^n, where n is the haploid number. If diploid is 10 (2n=10), then haploid is 5 (n=5). Thus, 2^5 = 32 combinations. Answer 'B' (32) is correct. Rationale: Each chromosome segregates independently (Mendel’s Law of Independent Assortment), so with 5 chromosome pairs, there are 2 choices (maternal or paternal) per pair, yielding 32 unique gametes.
Question 2 of 5
Which one of the following pairs is mismatched?
Correct Answer: C
Rationale: Down syndrome is 47, XX, +21, not +18 (C is mismatched). Rationale: Patau is +13 (A), Edwards is +18 (B), but Down is +21, making 'C' incorrect.
Question 3 of 5
Which of the following human triploid is possible to be found in adults:
Correct Answer: B
Rationale: Triploidy is incompatible with adult life (B). Rationale: 69, XXY (not listed) or similar triploids (3n) occur but are lethal or result in miscarriage. 92 (4n) or 23 (n) don’t fit triploidy (3n=69). Adults don’t survive triploidy.
Question 4 of 5
In the routinely performed karyotype (G-banding). Which of the following would you expect to have more clinical impact and lead to a disease?
Correct Answer: D
Rationale: Deletion of a light band (D) has more impact. Rationale: Light bands (euchromatin) are gene-rich; deletions (loss of function) often cause disease (e.g., 5p-). Duplications (A, B repeated) may be milder; single-band changes can matter (C false).
Question 5 of 5
The shortest stage in cell cycle:
Correct Answer: A
Rationale: M phase (mitosis) is the shortest, typically 1–2 hours in a 24-hour cycle. 'A' is correct. Rationale: G1, S, and G2 (interphase) last longer (hours each), while GO is a quiescent state, not a timed phase. Mitosis is rapid, with visible stages like metaphase lasting minutes.