Question

In recombinant DNA technology, the term vector refers to

• A. the enzyme that cuts DNA into fragments
• B. an organism capable of transmitting infectious disease pathogens
• C. a plasmid used to carry DNA into a living cell
• D. origin of replication

Answer 1

The correct option is C a plasmid used to carry DNA into a living cell

Recombinant DNA technology (rDNA technology) is a technique that alters the phenotype of an organism when a genetically modified vector is introduced and incorporated into the genome of the host.

In rDNA technology, a vector is a DNA molecule that acts as a vehicle to carry a desired DNA sequence into a host cell as a part of a molecular cloning procedure.

Plasmids are used as vectors because they can carry a foreign DNA fragment when inserted into it.

Plasmids are autonomously replicating circular extrachromosomal DNA in bacteria and are physically separated from chromosomal DNA.

Restriction enzymes are called molecular scissors as they cleave/cut DNA at or close to specific recognition sequences known as restriction sites. These enzymes make a single incision on each of the two DNA strands to generate restriction fragments. These enzymes are also called restriction endonucleases.

Origin of replication (ori) is a sequence from where replication starts and any piece of DNA when linked to this sequence can be made to replicate within the host cells.

In biology, the term vector also refers to organisms like insects (mosquitoes) that are capable of transmitting infectious disease pathogens among humans or between animals and humans. But in recombinant DNA technology, vector refers to molecule that acts as a vehicle to carry a desired DNA sequence.