Final answer:
A chromosomal translocation is the region where two chromosome pieces break and re-attach to other chromosome pieces. Translocations occur when a segment of a chromosome dissociates and reattaches to a different, nonhomologous chromosome.
Step-by-step explanation:
The region where two chromosome pieces break and re-attach to other chromosome pieces is called a chromosomal translocation. Translocations occur when a segment of a chromosome dissociates and reattaches to a different, nonhomologous chromosome. They can have benign or devastating effects depending on how the positions of genes are altered with respect to regulatory sequences.