Zoology - Biotechnology - Principles and Processes Question with Solution | TestHub

Plasmids and bacteriophages are commonly used vectors. The vector should have a few (or) at least one unique recognition site to link the foreign/alien DNA. Transposons are also frequently used as cloning vectors (the bacteriophage lambda is important in molecular biology because it is used in constructing vectors for gene cloning. Plasmids do this as well, but bacteriophages have an advantage over plasmids. Plasmids are circular, independently replicating, double-stranded DNA, most often found in bacteria. They replicate quickly and are easily manipulated in the laboratory. Plasmids are typically 2-10 thousand base pairs in size (Corbley, 1999). While this small size allows plasmids the two aforementioned attributes, it also means that plasmids are limited in the DNA fragments they can clone. They are typically limited to fragments around 5 thousand base pairs (King, 2002). While plasmids are great vector vehicles for many molecular endeavours, if the fragment to be cloned is larger than the available insertion space of the plasmid, the plasmid vector will probably not transfer the fragment of DNA successfully). Disarmed retroviruses are used as vectors in animals.