Which statement regarding plasmid-cloning vectors is CORRECT?
A) Circular plasmids do not require an origin of replication to be propagated in E. coli.
B) Foreign DNA fragments up to 45,000 base pairs can be cloned in a typical plasmid.
C) Plasmids do not need to contain genes that confer resistance to antibiotics.
D) Plasmid vectors must carry promoters for inserted gene fragments.
E) The copy number of plasmids may vary from a few to several hundred.

Question

Quizplus · Accepted Answer

The copy number of plasmids may vary from a few to several hundred. Options A, B, C, and D are incorrect statements. Plasmids require an origin of replication to be propagated, foreign DNA fragments up to 20,000 base pairs can be cloned in a typical plasmid, plasmids commonly contain genes that confer resistance to antibiotics, and plasmid vectors do not always require promoters for inserted gene fragments.

Which Statement Regarding Plasmid-Cloning Vectors Is CORRECT