NEETZoologyBiotechnology - Principles and Processes
Which of the following statements regarding cloning vectors is incorrect?
Options
- AThe 'ori' sequence is responsible for controlling the copy number of the linked DNA.
- BPlasmids are single-stranded linear DNA molecules that replicate under the control of genomic DNA.
- CAny piece of alien DNA linked to the 'ori' sequence can be made to replicate within the host cells.
- DPlasmids are autonomously replicating, extrachromosomal circular double-stranded DNA molecules.
Correct answer
B. Plasmids are single-stranded linear DNA molecules that replicate under the control of genomic DNA.
Step-by-step solution
Plasmids are small, circular, double-stranded, extrachromosomal DNA molecules that replicate autonomously, independent of the genomic DNA. The origin of replication ('ori') is a specific DNA sequence responsible for initiating replication. Any piece of alien DNA linked to this sequence can replicate within the host cell. The 'ori' also controls the copy number of the linked DNA. Therefore, if one wants to recover many copies of the target DNA, it should be cloned in a vector whose origin supports a high copy number