cloning vector

A cloning vector is a small DNA vehicle that carries a foreign DNA fragment. The insertion of the fragment into the cloning vector is carried out by treating the vehicle and the foreign DNA with the same restriction enzyme, then ligating the fragments together. There are many types of cloning vectors. Plasmids and bacteriophages (such as phage λ) are perhaps most commonly used for this purpose. Other types of cloning vectors include bacterial artificial chromosomes (BACs) and yeast artificial chromosomes (YACs).
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a circular DNA molecule in which foreign DNA is inserted for replication in an appropriate host organism.