8. Which of the following is obtained using processed mRNA molecules as a template?
A.rDNA
B.mDNA
C.cDNA
D.tDNA

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9. Vectors are
A.molecules that degrade nucleic acids
B.molecules that help in replication
C.molecules that are able to covalently bond to and carry foreign DNA into cells
D.molecules that protect host cells from invasion by foreign DNA

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10. What is the normal role of restriction endonucleases in bacterial cells?
A.To degrade the bacterial chromosome into small pieces during replication
B.To degrade invading phage DNA
C.To produce RNA primers for replication
D.All of the above

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11. Which of the following is not commonly used as vector?
A.Artificial chromosome
B.Cosmid
C.Fungi
D.Plasmid

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12. A short molecule containing 2-20 nucleotide is
A.plasmid
B.vector
C.oligonucleotide
D.mononucleotide

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13. Enzymes that recognize and cleave specific 4 to 8 base pair sequences of DNA are
A.DNA ligase
B.helicases
C.restriction endonucleases
D.DNA gyrase

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14. Which of the following vector can maintain the largest fragment of foreign DNA?
A.YAC
B.Cosmid
C.Plasmid
D.Phage

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