Final answer:
Recombinant DNA is an artificial combination of DNA from different species and is used to produce unique proteins. It's created using recombinant DNA technology and may require specific vectors for proper expression.
Step-by-step explanation:
A molecule that consists of DNA from one organism combined with the DNA from a member of another species is referred to as recombinant DNA. This is achieved through recombinant DNA technology, which involves cutting DNA from one organism and inserting new pieces of foreign DNA from another organism. This creates new combinations of genetic material, leading to chimeric molecules that do not occur in nature. Such DNA is used to produce recombinant proteins, and plasmids are often the vectors used to facilitate this process. However, not all plasmids can express genes; they may need to be transferred into another host that is more suitable for gene expression, and their activity can be regulated by environmental factors to control the expression of the recombinant proteins.