Transgenic animals are produced by
biologists use to join two dna molecules together.
during a cell takes in dna from outside the cell.
small, circular dna molecules that are found in bacterial cells are called

Transgenic animals are produced by injecting the desired gene into the pro-nucleus of a fertilized mouse egg.
Biologists use plasmids to join two DNA molecules together. 
During transformation , a cell takes in DNA from outside the cell. 
A plasmid is a small DNA molecule within a cell that is physically separated from a chromosomal DNA and can replicate independently. 

Active site is where they touch.