Question

In recombinant DNA technology, antibiotics are used

• A. As selectable markers
• B. To keep media infection-free
• C. As sequence where replication starts
• D. To select the healthy vector

Answer 1

The correct option is A

As selectable markers

The correct option is A.

The explanation for the correct answer:

1. In recombinant DNA technology, antibiotics are used as selectable markers.'
2. Recombinant DNA technology is the altering of genetic material outside the organism to obtain enhanced or desired characters in them.
3. The selectable markers are part of the cloning vectors which are antibiotic-producing protein genes.
4. In Recombinant DNA technology Bacteria are subjected to the introduction of a foreign gene under recombinant DNA technology they are grown on a medium containing the antibiotic.
5. The bacteria which can grow on that medium show successful incorporation of the foreign gene.
6. The selectable markers help in identifying and eliminating non-transformants. Hence selectively permits the growth of transformants.
7. Genes that transfer antibiotic resistance are usually used as selectable markers.
8. Selectable markers confer resistance to the bacteria from that particular antibiotic.
9. Common selectable markers used are ampicillin, kanamycin, chloramphenicol, tetracycline, etc.

The explanation for incorrect answers:

Option A:

Antibiotics are used against infection in a living being. But in recombination DNA technology antibiotics are used as selectable markers.

Option B:

1. In recombinant DNA technology, DNA replication initiates at specific points known as origins, where the DNA double helix is unwound.
2. A primer, a short segment of RNA act as an initiation point for the new DNA synthesis.
3. Selectable markers are not involved in the replication.

Option C:

1. A vector DNA is usually a plasmid or virus.
2. It carries a particular DNA segment to the host cell. It is done in cloning or recombinant DNA technique.
3. They are used to carry the desired gene into the host cells.
4. Vectors replication is independent of chromosomal DNA

Final answer: In recombinant DNA technology, antibiotics are used as selectable markers.