What is the difference btw. replication & duplication?
Apart from the answer provided by your friend, I would like to add that replication is the process in which one strand of the daughter DNA molecule is similar to that of the parent while the other strand is complementary to the parent strand. In duplication strands of DNA are identical to that of parents.
In genetics, replication is the copying of genetic material so that there are two copies. Duplication is when a part of the chromosome is repeated on itself, it is an error that can occur in DNA replication.
Ex. Replication: ABCDEFG ---> ABCDEFG & ABCDEFG
Gene with Duplication: ABCDEFGEFG