Which of the following karyotypes is an example of aneuploidy?

Correct Answer: C

Rationale: Aneuploidy is an abnormal number of chromosomes. 69,XXX (triploidy) is aneuploid; 46,XX is normal diploid, 23,X is a gamete, 92,XXXX is tetraploid, and 90,XX is not viable.

Correct Answer: A

Rationale: A linkage map uses recombination frequencies to determine the relative order of genes on a chromosome.

Correct Answer: B

Rationale: The Y chromosome’s SRY gene determines maleness, as seen in conditions like 47,XXY (male) vs. 45,X (female).

Correct Answer: C

Rationale: Cancer cells proliferate uncontrollably and can become immortal (e.g., HeLa cells), evading normal cell death.

Correct Answer: A

Rationale: The Philadelphia chromosome (t(9;22)) creates the BCR-ABL fusion gene in chronic myeloid leukemia.