ATI RN
Pediatric Genetic Questions
Question 1 of 5
All of the following regarding telomeres is true EXCEPT:
Correct Answer: C
Rationale: Telomeres don’t code for genes (C is false). Rationale: Telomeres are TTAGGG repeats (A), shorten with replication (B), and protect chromosome ends (D). They’re non-coding, and telomerase activity is high in cancer (E), making 'C' the exception.
Question 2 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 3 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 4 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.
Question 5 of 5
Which of the following cannot used in karyotype?
Correct Answer: D
Rationale: Erythrocytes (D) cannot be used for karyotyping as they lack nuclei. Rationale: Karyotyping requires dividing cells with chromosomes; chorionic villi, lymphocytes, and bone marrow provide mitotic cells, but mature erythrocytes are enucleated.