The process in which chromosomes exchange materials through the breakage and reunion of their DNA molecule is known as

The process in which chromosomes exchange materials through the breakage and reunion of their DNA molecule is known as Crossing over.
Crossing over is a cellular process that happens during meiosis when chromosomes of the same type are lined up.
When two chromosomes one from the mother and one from the father line up, parts of the chromosome can be switched. The two chromosomes contain the same genes but may have different forms of the genes.