Which of the following is not a desirable feature of a cloning vector ?
Answer: (D) Presence of two or more recognition sites. Answer: (d) Presence of two or more recognition sites Solution: A good cloning vector should have very few — preferably single — recognition sites for commonly used restriction enzymes; presence of more than one recognition site generates several fragments and complicates gene cloning, so it is NOT a desirable feature.
- A.Presence of origin of replication
- B.Presence of a marker gene
- C.Presence of single restriction enzyme site
- D.Presence of two or more recognition sites✓
Correct Answer
(D) Presence of two or more recognition sites
Solution & Explanation
Answer: (d) Presence of two or more recognition sites Solution: A good cloning vector should have very few — preferably single — recognition sites for commonly used restriction enzymes; presence of more than one recognition site generates several fragments and complicates gene cloning, so it is NOT a desirable feature. Origin of replication, a selectable marker gene, and a single restriction (cloning) site are all desirable features. NCERT Reference: Ch 9, p.169, line(s) 31-35 — "Presence of more than one recognition sites within the vector will generate several fragments, which will complicate the gene cloning"