Chromosomal aberrations — The exchange of segments between non-homologous chromosomes is best known as what?

Introduction / Context:
Chromosomal structural changes can profoundly affect gene expression, fertility, and evolution. Distinguishing among crossing over, recombination, and translocation is core genetics knowledge and has practical implications in plant breeding and medical cytogenetics.

Given Data / Assumptions:

• “Non-homologous chromosomes” means chromosomes that do not share the same gene order.
• Segment exchange between non-homologs alters linkage groups and can create novel gene juxtapositions.
• Standard meiotic crossing over occurs between homologs, not non-homologs.

Concept / Approach:
Translocation refers to the movement of a chromosomal segment to a non-homologous chromosome. It can be reciprocal (mutual exchange) or non-reciprocal (one-way transfer). In contrast, recombination is a broad term largely applied to exchange between homologous chromatids during meiosis (crossing over) or to molecular DNA exchange events.

Step-by-Step Solution:

Verification / Alternative check:
Classical cytogenetics (e.g., wheat–rye translocations) demonstrates non-homologous exchanges used in breeding for disease resistance.

Why Other Options Are Wrong:

Common Pitfalls:
Equating any exchange with “crossing over.” Context (homologous vs non-homologous) is decisive.

Final Answer:
Translocation.