Final answer:
A random piece of DNA is called a transposon. Transposons are small DNA molecules that have the ability to independently excise from one location in a larger DNA molecule and integrate into the DNA elsewhere.
Step-by-step explanation:
A random piece of DNA is called a transposon. Transposons are small DNA molecules that have the ability to independently excise from one location in a larger DNA molecule and integrate into the DNA elsewhere. They can move around within the genome and can have significant effects on genetic variation and evolution.